Abstract: A reclosable, cuboidal folding box, which can be manually assembled, having a single closure flap which comprises a double-walled hanging tab with hanging means and separate tabs to stabilize the box, and form a tamperproof closure.

Abstract: A container which is useful in storing articles which are to be recycled until the filled container is returned to the original manufacturer or recycling depot. The container has a port through which cartridges may be conveniently inserted to be stored. The container, which has a plastic bag in communication with the port, is preferably supplied to the consumer as a folded blank and which may be easily erected by the consumer to form a recycling container.

Abstract: An apparatus for packaging and shipping biological fluid samples collected in vials is disclosed. The apparatus includes an absorbent body for supporting a plurality of vials, a packaging container for surrounding and protecting the absorbent body when at least one of the vials is received and supported therein, a shipping container for surrounding and protecting at least one of the packaging containers and a shipping carton for surrounding and protecting the shipping container during shipment from a facility where the biological samples are collected to a facility for analyzing the biological samples. The apparatus in accordance with the invention is particularly useful in clinical drug trials, phases 1 to 4. The apparatus is designed to be used with robotic analyzers which automatically locate and remove the vials from the absorbent body in a predefined order in accordance with an index associated with the top surface of the body.

Abstract: A box for containing goods during storing, delivering, mailing, or shipping. The box has at least one closure panel secured to a body panel to selectively close an opening in the box. A locking tab on the box selectively engages a panel of the closed box, so that the box cannot be opened without separating the locking tab and thereby providing visible evidence of the opening. The locking tab includes an opening tab to separate at least part of the locking tab in a predetermined manner, by pulling the opening tab.

Abstract: A clamshell type paperboard container formed from a unitary blank of paperboard. Two embodiments are described. In the first, the container is square and the lid includes four triangular panels meeting at an elevated and central common point. In the second, the container in rectangular and the lid includes two triangular panels and two trapezoidal panels, and the central elevated portion of the lid includes an elongated ridge or rib. These constructions prevent stacking and hence inadvertent crushing of a closed and filled container. The slanting sides of the lids yield an easel effect for graphics thereon.

Abstract: A lined, flip top style, paperboard carton with an integral hinged cover, that includes a positive side lock arrangement between the carton body and cover on each side of the carton, wherein each of the minor upper inner closure flaps has a first section secured to the inner surface of the major upper outer closure flaps and a second section depending from the first section and having extending there through an opening adapted to receive and retain a tab, projecting outwardly from the upper edge of a carton liner secured to certain of the carton side walls, to maintain the cover in a closed position upon reclosure of the carton cover after initial opening.

Abstract: A food container consisting of a top and a bottom having obliquely angled side elements is disclosed. The container may be cut from a single blank of container material and formed into a hingedly connected top and bottom. When the top and bottom are open and substantially coplanar the obliquely angled sides permit multiple boxes or containers to be nested within one another for efficient stacking. A preferred embodiment includes tops and bottoms with eight side elements comprising one piece side elements and side elements having overlapping panels. When closed, the top side elements overlap the bottom side elements. The container also includes a locking tongue and opening which receives the tongue. A tab may be provided to assist in moving the tongue to disengage it from the opening.

Abstract: A single latch assembly integrally with the front walls of the tray and cover of a clamshell carton and positioned solely to one side of the transverse center line of the front walls in the area of maximum strength of each front wall. The latch assembly component on the tray includes an inwardly directed elongate flange and an outwardly directed tongue at the top edge of the tray front wall positioned solely between the central area of the top edge and one end thereof. The latch assembly component on the cover includes an elongate aperture defined through the cover front wall immediately adjacent the top panel of the cover.

Abstract: A single piece container and method for making the same are presented. The container has an opening and a body and includes first and second pairs of opposing covering flaps and a pair of opposing handles. The covering flaps cover the container body opening so as to keep the container contents in place.

Abstract: A display tray formed from corrugated or solid fiber paper is useful for packaging, shipping, displaying and transportation of various goods. The tray includes a planar bottom which has a central and two extreme sections formed by a pair of parallel score lines. Opposing ends and sides are joined to the bottom and each side includes a pair of vertical and angular score lines which intersect proximate the bottom score lines for folding purposes. The tray can be easily changed from an open to either a partially or fully closed tray by manually bending along the sides at the described score lines to rotate the end assemblies.

Abstract: A box is disclosed having a pivot lid and a skirt. The skirt has an internal edge cooperating in a snap locking manner with a folded-over flap at the front edge area of the box mouth. This flap protrudes from an edge area which, as a whole, is resiliently depressible into the box, whereby a snap locking is achieved which will be substantially independent of the manufacturing tolerances of the box. The locking and, in particular, the release of the locking by the opening of the lid will take place in a manner that is very convenient for the user, because the spring action after the release of the locking will contribute to the opening of the lid.

Abstract: A fast food carton including a tray with peripheral walls integral with a bottom panel and individually foldable relative thereto between a first position substantial coplanar therewith and a second folded position forming a peripheral wall thereabout, and a lid integral with one of the tray walls and selectively foldable to cover the tray with the tray walls retained in the folded position within the lid. The carton further includes a lock assembly having a tongue integral with the tray front wall and outward projectable through a slot formed in the lid, the lid having openings defined therein for facilitating manual manipulation of the lock assembly for release.

Abstract: A unitary blank having a multiplicity of fold, cut, and score lines permitting the blank to be folded along the fold and cut lines to form a container attached along a first score line to a display panel adapted to be hung from an arm of a merchandising display unit. The blank defines at least one locking slot and further having a tab connected along a first folding line to a first panel and connected to the display panel along a second score line. The tab is insertable in the slot when the display panel is separated from the container to close the top of the container with the first panel.

Abstract: A clamshell type container is formed from a unitary blank of paperboard. The central portion of the crown of the carton is convex upwardly and the crown carries inwardly concave opposite side walls. The four corners of the crown are each provided with triangular gussets to permit slight deformation of the crown both upon stacking of the open cartons and upon closing the crown down onto the lower tray part of the carton. The tray side walls are curved or recessed downwardly so as to form line contact with a respective crown side wall, such contact defining a seal and inhibiting warm air loss when a warm foodstuff is placed in the carton.

Abstract: A blank and carton formed therefrom including a pentagon-shaped bottom panel, first, second and third side wall panels integral with three edges of the bottom panel with fold lines defined therealong, fourth and fifth side wall panels integral with opposed edges of the third side wall panel, a top panel integral with the outer edge of the third side wall panel opposed from the bottom panel along a defined fold line, and glue flaps on selected edges of the panels whereby upon a folding of the panels an erected receptacle with folding lid is formed.

Abstract: A folded paperboard carton including first and second longitudinally aligned compartments with a common base panel, the first compartment including a cover integral therewith and foldable to overlie the first compartment, the second compartment extends above and opens upwardly relative to the closed first compartment with the inner wall of the cover dividing the two compartments.

Abstract: A box for containing goods during storing, mailing, or shipping. The box has at least one end panel secured to a body panel by a locking tab extendable through a slit in a closure flap of an end panel, so that the end panel cannot be unsecured without providing visible evidence of tampering. The locking tab is foldable for insertion through the slit, after which a surface of the locking tab engages the underside of the flap to prevent withdrawing the locking tab through the slit. Flanges on the locking tab engage the locked box, further preventing withdrawal of the locking tab. The locking tab is joined to the remainder of the box by perforated lines of selective weakness, which tear to provide visible evidence of tampering with the locking tab.

Abstract: A pretaped container blank which may be quickly and easily formed into a three-dimensional container without the need for additional components or tools. The container blank includes (i) a plurality of interconnected panels, and (ii) a plurality of closure flaps including a carrier flap hingedly connected to at least one of the panels. The tape structure is attached to the container blank and includes (i) a release surface on the carrier flap, and (ii) a length of closure adhesive tape extending over substantially the entire length of the release surface and a distance across the panel or flap to which the carrier flap is connected sufficient for the tape to remain attached to the container blank upon removal of that length of the tape from the release surface. Several embodiments of container blanks and tape structures are disclosed.

Abstract: A corrugated board package formed from a blank of a kind having a single component to define a base, sides and top. The blank has a substantially square or rectangular base portion limited by fold lines and/or cuts or cutouts and four separate peripheral portions. The peripheral portions include an opposed pair of the peripheral portions being foldable to create first opposed side walls and subsequent to assembly being further folded to provide at least part of the top of the package, those portions of the peripheral portion to form the opposed side walls being extended at one end in a direction parallel to the fold line and/or cut or cutout connection to the base portion to define a flap which, either in a folded or unfolded condition, can be folded at right angles from the side wall to assume a position as part of the structure of an end wall normal to each opposed side wall with a projection or projections formed by part of the flap, whether a fold created periphery or otherwise, directed upwardly.

Abstract: A hinged lid box having an innerframe and interlocking means for maintaining the box substantially closed. The interlocking means includes a panel of material including a tab that is secured to the inside of the front panel of the lid so that the tab is opposed to but not secured to the lid surface whereby the tab is disposed to pass inside the innerframe during closure. The innerframe is thus frictionally engaged by the tab and the opposing surface of the front panel of the lid to retain the lid closed. The tab may be formed by a slit in the panel of material and provided with a score line to facilitate bending the tab at the desired location to engage the innerframe. The tab also may be formed by cutting a notch in the panel, thereby providing a space between the tab and the panel from which the tab is cut. The notch may be provided with a configuration that facilitates inserting the tab behind the innerframe. Means for raising the tab a distance above the surface of the panel of material also may provided.

Abstract: A one-piece box is disclosed which is foldable from a flat blank to an erect box. The box is provided with a corner interlock comprising a tab on the side wall extending through an opening in the front wall. A cover interlock is provided using a single panel front wall having a tab which extends through an opening in the cover. The box blanks may be cut from a single board in side-by-side nested relationship with a wall or flap of one box blank being of reduced height and receiving a protruding portion of the corresponding wall or flap of the adjacent box blank.

Abstract: A stackable package for storing fruit or like objects is in the form of a tray, carton or case (1) with a pair of panel supports (6) provided adjacent each end wall (3). The panel supports (6) substantially bear the weight of like packages positioned thereabove when a stack of packages is formed. The panel supports have a pair of protrusions (8) on the upper edge thereof and a pair of recesses (14) adjacent the lower edge thereof wherein the protrusions can be positioned in the recesses of a package positioned thereabove when two or more packages are stacked. So that a stiff protrusion is provided, the panel support is formed from dual arch corrugated board having two layers of corrugated board joined at the protrusions. The wedge-shaped protrusions (8) thus produced can be readily indexed in adjacent recesses (18) in the base of a carton stacked above, and in top lid apertures (23, 24) in the closed position.

Abstract: A box for containing goods during storing, delivering, mailing, or shipping. The box has at least one end panel secured to a body panel by a locking tab and slot assembly so that the end panel cannot be unsecured without providing visible evidence of tampering. The leading edge of the locking tab has at least a partially tapered profile when the tab is folded for insertion through the slot. The slot may be curved to provide additional abutment between the associated locking tab and slot assembly. The container may have decorative motifs printed on the exterior surface to resemble a gift-wrapped box or a box having a unique or characteristic graphic design.

Abstract: A paperboard container which displays particular utility for the packaging of fast food products is formed from a unitary blank of paperboard. The blank, typically, employs an automatic bottom, i.e., a bottom which is automatically formed upon opening the container from a folded or flattened configuration. The container is characterized by side webs between the top edges of the end panels and the top cover panel. Upon folding the top cover panel down to close the container, after being loaded with food, each side web forms a point or apex along its edge, this apex then tucked into a complementary slit in a respective end panel. Each side web is in frictional, surface to surface engagement with a respective end panel. Further, the top closure cover is provided with a friction latch cooperating with the front wall panel to thereby yield three points of frictional engagement to maintain the container in its closed position prior to being opened by the consumer.

Abstract: A clamshell type carton is provided with a cut along the hinge score line connecting the upper cover and lower tray portions. A second cut is placed in the back panel of the carton, above or below the hinge score line cut, wherein the second cut is a continuous curve having a first end point located in the back panel and a second end point intersecting the cut along the hinge score line. The second cut is utilized to facilitate the easy opening and closing of the carton without buckling occurring in the back panel in the region of the hinge score line.

Abstract: A container formed by wrapping a slotted flexible sheet about rigid end panels having projections that extend through the slots. The projections include stacking projections which engage recesses in the end panels of adjacent stacked containers and support projections at the corners. The support projections engage each other when the containers are stacked to provide resistance to lateral loading. At least one end of the flexible sheet terminates in the top panel and engages a wedge-shaped projection on the end panels to lock that end of the sheet in place. The other end may be similarly locked in place or may overlap the first end and be held in place by a tab and slot arrangement. Alternatively, the other end portion of the sheet may include a lid which is held in place by mechanical tabs, while intermediate edges spaced from the end engage the wedge-shaped projections.

Abstract: A clam shell carton having a hexagonal tray with a similarly configured hexagonal cover integrally hinged thereto. The tray and cover, outward of hinge joined inner walls thereof, include alternating high and low peripheral walls with projecting locking lugs on selected ends of the high walls. The high and low walls on the cover respectively overlap the low and high walls on the tray with the locking lugs on the cover releasably interlocking with the locking lugs on the tray.

Abstract: A re-usable, recyclable, reversible carton is made from recyclable plastics material and is formed from a carton blank adapted for erection without the need for additional closure devices such as glue or staples. The plastics material may be polyethylene and printing on at least one surface may be by use of UV inks on a roughened surface with a view to maximum longevity of the printing. The carton is erected from a knock-down carton blank having releasable engagement tabs and slots to releasably maintain the carton in an erected condition. A two part lid is provided, each part of which may be folded down the side of the carton to allow for the possibility of using the carton for open storage.

Abstract: A carton including a hexagonal tray with a complementary hexagonal cover integrally hinged thereto for closing thereover. A dual locking system between the tray and cover includes projecting locking lugs coplanar with the front wall of the tray and extending beyond adjoining tray side walls for interlocking engagement with corresponding lugs on side walls of the cover which extend beyond the cover front wall. The locking assembly also includes headed upwardly extending tabs on selected tray side walls which engage through corresponding slots in the cover top panel to lock the top panel downwardly against the upper edges of the side walls from which the tabs project.

Abstract: A clamshell type carton is provided with a cut along the hinge score line connecting the upper cover and lower tray portions. Either a second cut in the back panel of the carton, above or below the hinge score line cut, or a cut-out slot encompassing the hinge score line cut, is utilized to facilitate the easy opening and closing of the carton without buckling occurring in the back panel in the region of the hinge score line.

Abstract: A box includes one or more cover elements having a closure panel from which a tongue extends. The tongue can be introduced into the box as the cover is closed and through the tongue an elongated window is provided, at and near which a hole is formed through the cover closure panel. Under the cover closure panel there are provided flaps which project from one or more main panels of the box. The flaps being folded and arranged under the closure panel as the related cover is closed. From at least one of the flaps there extends a hook shaped tooth which projects in the window and is locked therein. The tooth being separated by its respective flaps by way of a preset breakage line, so that the tooth operates as a seal element and is torn from the flap as the cover is opened. The presence of the tooth and accordingly the untampered condition of the box can be checked through the hole formed through the closure panel.

Abstract: A paperboard clamshell carton includes a tray and a cover, hingedly connected and latched in the closed position by cooperating latching members. Detents, extending forwardly from adjacent the upper corners of the front wall of the tray, and detent engaging slots and tabs in the cover, located adjacent the lower corners of the front wall of the cover, releasably engage when the cover is folded shut over the tray. The forwardly extending detents are of double thickness, being formed by overlapped extensions of the glue flaps and side walls of the tray.

Abstract: A stackable package for storing fruit or like objects is in the form of a tray, carton or case (1) with a pair of panel supports (6) provided adjacent each end wall. The panel supports (6) substantially bear the weight of like packages positioned thereabove when a stack of packages is formed. The panel supports have a pair of protrusions (8) on the upper edge thereof and a pair of recess (14) adjacent the lower edge thereof wherein the protrusions can be positioned in the recesses of a package positioned thereabove when two or more packages are stacked. So that a stiff protrusion is provided, the panel support is formed from dual arch corrugated board having two layers of corrugated board joined at the protrusions. The wedge-shaped protrusions (8) thus produced can be readily indexed in adjacent recesses (18) in the base of a carton stacked above and in top lid apertures (23, 24) in the closed and open positions.

Abstract: A reusable, recyclable carton is made from recyclable plastics material and has a closure which does not require glue, staples or other non-recyclable closing elements. The plastics material may be polyethylene. The carton is erected from a knock-down carton blank having releasable engagement tabs and slots to releasably maintain the carton in an erected condition. A two flap lid is provided, the flaps meeting on a line joining opposing walls of the carton. A flange rises from each of the opposing walls adjacent the joining line of the lid flaps. The flange is joined to its respective wall along only part of its length so that it has free ends. The flange may be bent over to overlie the lid flaps and its ends may be tucked into slots in the lid flaps for that purpose.

Abstract: An asparagus carton and a unitary blank for forming it. The blank is of corrugated paperboard. The carton interior is tapered along opposite side walls by virtue of slanting side spacer panels. This yields a trapezoidal configuration of a part of the carton interior to more nearly correspond to the tapered form of a mass of asparagus. The carton is preferably loaded from the bottom. The asparagus may be inspected by opening a side wall panel, and may also be opened from the top. In addition to providing slanting side walls, the side spacer panels permit the loaded carton to be lifted through side wall openings without contacting the asparagus. In a first embodiment, the bottom of the carton may be opened by releasing a bottom tongue and slot latch arrangement, while in a second embodiment the bottom of the carton is defined by known interlocking panels.

Abstract: A hinged lid box having an innerframe and rounded corners and means for maintaining the box substantially closed. The means includes a second front panel of material affixed in superposition to the interior front panel of the box lid to engage the innerframe of the box, providing increased structural support and frictional forces that retain the box in a closed position. The second panel of material has approximately the same width at the lid panel and a height that is greater than 50% and less than 100 % of the height of the box lid. The panel also may have tabs extending from the panel into the rounded corners of the box so that the tabs are interposed between the innerframe corners and the lid corners when the lid is closed.

Abstract: The present invention comprises a one-piece blank for forming a shallow triangular carton. The blank includes a bottom portion having converging paired sidewalls hinged thereto. A third wall is hinged to the bottom and to a cover. In one embodiment the paired sidewalls have upwardly protruding tabs for engaging the cover, and the cover exhibits tab engaging openings therein. In another embodiment, the cover openings converge to define a flexing peripheral edge for frictionally engaging the sidewalls at their conjunction.

Abstract: A carton comprising a cover structure formed from a cut and scored flat blank of carton material. The cover structure includes a top wall having a plurality of side walls extending therefrom along a straight common fold line therebetween within a plane defining an interior included angle with the top wall of less than 180.degree.. The cover structure includes a plurality of over center toggle action tabs having indicia operatively associated with each tab. Each over center toggle action tab is defined by cuts and edge lines formed in the top and side walls so as to contain a predetermined length of the common fold line therebetween which divides the tab into two tab sections. The cuts enable the peripheral edge portion of the tab defined thereby to move toward and away from the adjacent cut top and side walls while the peripheral edge portions of the tab defined by said edge lines hinge with respect to the adjacent top and side walls.

Abstract: A collapsible box that can be formed from a one-piece sheet of foldable paperboard and that has opposed side and end walls and a top wall or cover that includes a pair of sections hinged to the end walls and that can be kept closed by snug, interlocking, frictional engagement between inner and outer panels of the side walls.

Abstract: A clamshell carton formed from two integral blanks of sheet material. The front wall of the upper clamshell carries a latching aperture. The front wall of the lower clamshell half carriers a latch release panel, the latter carrying a horizontally despaired latching tongue normally engaged in the latching aperture to maintain the clamshell in a closed configuration. The latch release panel is normally resiliently biased to maintain the latch tongue engaged. The front wall of the upper clamshell half is provided with a recess along a free edge, the recess permitting direct finger force to be applied to the latch release panel to open the carton by disengaging the latch.

Abstract: A packing box with self-locking closure, the packing box comprising a bottom portion including a plane having at least three adjacent sides and a lid portion including a plane having at least three adjacent sides, wherein at least one of the sides of the bottom portion includes a flap provided with a support and further wherein at least one of the sides of the lid portion opposite the bottom portion provided with a flap is provided with a flap holding element which can be combined with a guide in order to ensure that the box is automatically prevented from opening without outside intervention when the lid portion is placed over the bottom portion of the box.

Abstract: A clamshell or other hinged top cover type carton for hamburgers is provided with a divider sheet formed from paperboard or a paperboard laminate. The ends of the divider sheet extend laterally beyond the side edges of the carton. A bun heel and hot hamburger patty are located in the lower half of the container and a bun crown and various toppings are located in the top container half. The divider sheet separates the hot meat patty from the cooler toppings. For hamburger consumption, the user pulls a laterally extending edge of the divider sheet laterally away from the carton, the bun crown and toppings fall on to the hot hamburger patty and bun heel, thereby preparing the hamburger sandwich. The consumer now opens the carton to gain access to the sandwich.

Abstract: A carton erected from carton material in cut and scored blank form, the carton comprising a lower tray structure comprising a bottom wall having flap connected tray side walls folded upwardly from the bottom wall, and an easy-open easy-close cover structure having a top wall having flap connected cover side walls folded from the bottom wall including a corner wall extending from the top wall between two adjacent spaced apart end edges of two adjacent cover side walls within a plane extending at an angle with respect to the angularly related planes of the two adjacent cover side walls. The cover structure is retained in closed relation by an opening formed in the corner wall and tabs formed from a portion of carton material defining the tray structure at the interconnection of the two adjacent tray side walls.

Abstract: A preformed blank of corrugated sheet material for assembly of a container for fresh produce, and a container assembled from such blank and comprising a bottom, side walls reinforced at least at the corners of the container for enhancing its vertical compressive strength, a pair of top walls having container closure tabs formed therein and cooperating with registrable slots therein for frictional closure of the container. Each top panel has a pair of parallel elongated hand carry slots registrable with each other in a closed container position, the adjacent parallel edges of at least one pair of slots being connected to the sheet material and the remainder of the slot peripheries being perforated to form a pair of push-in flaps. At least one side wall has opening patterns spaced apart in the vertical and horizontal directions for visual inspection of the container contents and facilitating air circulation within the closed container.

Abstract: A container which can be constructed in one-piece or in two pieces. The container is preferably of corrugated paper-like material and is preferably of the "E-flute" type of corrugated material. The container includes a body member or body portion and a cover member or cover portion. The container includes a latch which automatically operates to latch the container in closed condition when the container is closed. The container has panels and walls which are relatively angular so that the opposing walls are in effective covering relationship when the container is closed. Also, the angular relationship between the panels and the walls permits a plurality of the containers to be nested and stacked in a stack having a minimum height.

Abstract: A carton having a tray and cover locked in closed position by means of a pair of detents extending forwardly and above the front wall of the tray. The detents are of double thickness being formed by overlapped extensions of the glue flaps and side walls of the tray. A pair of slots in the cover receives the detents in a closed position to lock the cover to the tray.

Abstract: A multi-compartment carton folded from a unitary cardboard blank and including a central partition defined by a pair of generally spaced partition panels. The opposed ends of the partition section incorporate laterally directed glue flaps which adhesively bond to opposed aligned pairs of side walls. The side walls, along each side of the formed compartments, in turn include projecting integral extensions which overlie and bond to each other above and independently of the glue flaps to provide a rigid interlock of the aligned walls and a rigid fixing of the compartments relative to each other. Closures, either unitary with the blank of the carton or as separate lids, close and segregate the defined compartments.

Abstract: A carton blank formed from a continuous sheet of material and capable of being easily folded into a self-supporting carton structure. A unique cover locking arrangement is provided whereby both lids forming the cover are independently locked against accidental opening without the aid of external fasteners and further provide superior protection for the contents of the carton against dust and moisture. The absence of external fasteners also make the carton more economical to manufacture and aesthetically pleasing to look at. The carton is also equipped with improved hand holes to facilitate balancing and carrying of the box when loaded.

Abstract: A portable disposable spray hood for receiving an article to be spray coated and capturing overspray from an aerosol container type spray device used to spray coat the article is formed from a plurality of connected panels foldable relative to each other between a set-up position wherein the panels cooperate to define the hood and a collapsed position wherein the panels cooperate to form a shallow box containing a supply of disposable paper liners used to line the base portion of the hood in its set-up condition.

Abstract: A stable box-like one-piece quick pack is formed from an inherently stiff but permanently bendable and shapeable flat material, with the pack comprising a baseplate, upwardly directed side walls extending from two opposite edges of said baseplate, and a rear wall which includes opposite a lid and a first front wall. The first front wall extends between a second front wall starting from the baseplate and the side edges of the side walls. Fold-over flaps formed on the side walls, and a push-in tongue provided on the second front wall extend into slits in the lid and in the first front wall, respectively. In one invention form, the flaps formed on the side walls are of a length greater than one-half the length of the front and back walls so as to overlap when folded toward each other, with one of the flaps being bent upwardly through a slit in the other flap to form a carrying handle.