Abstract: Floorboard and openable locking system therefor comprise an undercut groove on one long side and projecting tongue on an opposite long side of the floorboard. The undercut groove has a corresponding upwardly directed inner locking surface at a distance from its tip. Tongue and undercut groove are formed to be brought together and pulled apart by pivoting motion with a center close to the intersection between the surface planes and common joint plane of two adjoining floorboards. The undercut is produced by at least two disk-shaped cutting tools with rotary shafts inclined relative to each other to form first an inner part of the undercut portion of the groove and then a locking surface positioned closer to the opening of the groove. Installation method for a floor of such boards, manufacturing method for manufacturing the undercut groove and a wedge-shaped tool for laying of the floorboards is also disclosed.

Abstract: A housing structure includes a first plurality of wall panels which form a lower course and a second plurality of wall panels which form an upper course. Each of the wall portions is generally rectangular and includes integrally formed interlocking portions which facilitate attachment of adjacent lateral edges of the wall portions of the first plurality to each other. Integrally formed interlocking portions facilitate attachment of the panels in the lower course to the panels in the upper course. In addition, rectangular roof panels are provided to enclose the housing structure. The interlocking portions enable the panels to slide into an interlocked engagement configuration thereby forming a rigid structure without the need for tools.

Abstract: A two-ply flooring plank is disclosed having two layers or “plies” with a bottom layer having a grain that runs generally transverse to a top layer (i.e., “cross-ply”) to provide dimensional stability to the plank. The bottom layer includes a number of strips secured to the bottom of the top layer. The bottom layer strips are also placed with gaps between the individual strips of the second layer to allow flexibility of the flooring plank, which allows the flooring to more easily conform to irregularities in a subfloor upon which the flooring plank is mounted.

Abstract: A vented hollow translucent/transparent plastic block for use in wall construction includes a spectrally selective film laminate disposed therein to define two compartments within the plastic block and to establish an U-factor of 0.35 or less with a S.H.G.C. of 0.39 or less. A vent is disposed in a side wall of the plastic block in fluid communication with each of the compartments to alleviate any pressure increase/decrease within the plastic block and for discharging any condensation within the plastic block that may occur.

Abstract: A panel, for installation on a ceiling as a component of a matrix grid of similar panels, with the ceiling panels capable of being installed directly on sheetrock ceilings without the otherwise need for affixing a wooden structure to the sheetrock ceiling before affixing the ceiling panels.

Abstract: Flooring material comprising sheet-shaped floor elements with a mainly square or rectangular shape. The floor elements are provided with edges, a lower side and an upper decorative layer. The floor elements are intended to be joined by means of joining members. The floor elements are provided with male joining members on a first edge while a second edge of the floor elements are provided with a female joining member. The male joining member is provided with a tongue and a lower side groove while the female joining member is provided with a groove and a cheek, the cheek being provided with a lip. The floor elements are provided with a male vertical assembly joining member on a third edge while a fourth, opposite, edge is provided with female vertical assembly joining member. The floor elements are alternatively provided with a male vertical assembly joining member on a third edge while a fourth, opposite, edge also is provided with male vertical assembly joining member.

Abstract: A modular building system formed of blocks supported around a loadbearing pipe frame. The blocks include half cylinder protruding portions located at opposing ends of the blocks wherein the protruding portions of adjacent blocks form cylindrical fastener portions. Horizontally adjacent blocks form courses, and horizontal courses of blocks are stacked to form walls. The fastener formed by the protruding portions of a lower course extend through an aperture in the lower portion of blocks forming an upper course, and a retainer member is engaged with the fastener formed by the protruding portions to thereby lock an upper course block to two lower adjacent blocks. The retainer member is formed with a through hole for receiving a vertical pipe member in sliding engagement wherein the vertical pipe members carry vertical loads without substantially transmitting vertical loads to the blocks.

Abstract: The invention relates to a system for laying and mechanically joining building panels, especially thin, hard, floating floors. Adjacent joint edges (3, 4) of two panels (1, 2) engage each other to provide a first mechanical connection locking the joint edges (3, 4) in a first direction (D1) perpendicular to the principal plane of the panels. In each joint, there is further provided a strip (6) which is integrated with one joint edge (3) and which projects behind the other joint edge (4). The strip (6) has an upwardly protruding locking element (8) engaging in a locking groove (14) in the rear side (16) of the other joint edge (4) to form a second mechanical connection locking the panels (1, 2) in a second direction (D2) parallel to the principal plane of the panels and at right angles to the joint. Both the first and the second mechanical connection allow mutual displacement of joined panels (1, 2) in the direction of the joint.

Abstract: A parquet board with a groove and tongue edge profile comprising a projecting tongue (14) on at least one edge of each parquet board (10,12) and a receding groove (16) on at least one opposite edge of the parquet board. The top edge of the tongue (14) is provided with a projecting locking lip (24) running in the longitudinal direction of the tongue, and there is a corresponding locking recess (26) running in the longitudinal direction of the groove in the bottom edge of the groove-boundary-forming top groove cheek (28).

Abstract: A vented hollow translucent/transparent plastic block for use in wall construction includes a single aperture disposed along the lower edge of the plastic block for alleviating pressure within the plastic block and for discharging any condensation within the plastic block that may occur.

Abstract: The invention concerns hard panels for floor coverings, which are provided, at least on two opposite edges, with coupling devices made in one piece with the panels wherein similar panels may be coupled together to form a floor covering, wherein these coupling devices provide for an interlocking in a direction perpendicular to the plane of coupled panels, as well as in a direction perpendicular to the edges concerned and parallel to the plane of coupled panels. These coupling devices comprise a tongue and a groove. A lip which is situated on the bottom side of the groove is longer than a lip located on the top side of the groove. The edge which is provided with the tongue is made elastically flexible.

Abstract: The invention concerns hard panels for floor coverings, which are provided, at least on two opposite edges, with coupling devices made in one piece with the panels wherein similar panels may be coupled together to form a floor covering, wherein these coupling devices provide for an interlocking in a direction perpendicular to the plane of coupled panels, as well as in a direction perpendicular to the edges concerned and parallel to the plane of coupled panels. These coupling devices comprise a tongue and a groove. A lip may be situated on the bottom side of the groove may be longer than a lip located on the top side of the groove. The edge which is provided with the tongue is made elastically flexible.

Abstract: Each of a plurality of masonry article comprises a contoured first header, a contoured second header, a contoured front face, a back face, a contoured lower base and an upper base. The plurality of masonry articles has a plurality of holes extending from the lower base to the upper base. The contoured first header couples to the contoured second header of another plurality of masonry articles and the contoured lower base couples to the upper base of the other plurality of masonry articles so that an outward face of a portion of a wall assembled with the plurality of masonry articles has a mortar-like vertically oriented gap and a mortar-like horizontally oriented gap. A plurality of corner masonry article and plurality of alternative corner masonry articles similar to the plurality of masonry articles permit assembly of a portion of a corner section of the wall.

Abstract: A ramp member is provided for attachment with an edge of a floor mat to facilitate transportation of an object from a floor to an upper surface of the mat. A tab is provided which extends from the ramp member and defines a plane. Two projections extend from the plane of the tab out of alignment with the plane. Additionally, two cavities are formed in the ramp member adapted for receiving at least one of the two projections therein. A method of connecting ramp members is also included.

Abstract: A deck panel includes a generally planar body portion having an upper surface and first and second side surfaces on opposed sides of the upper surface. An elongated tongue extends outwardly from and along the first side surface. An elongated groove is defined in and extends along the second side surface, the groove being adapted to receive a second tongue. The deck panel is formed of a polymeric material.

Abstract: A device for connecting and locking structural panels, particularly floor panels, having a groove forming an upper lip and a lower lip over the entire length of at least one lateral border and with a tongue formed on the opposite lateral border corresponding to the groove. To lock panels that have been connected, the tongue is provided with at least one projection and the groove exhibits at least one indentation on the lip that faces the projection, which device is characterized by the indentation being longer than the projection, and on its lateral border (I3, I4) the lip provided with at least one indentation exhibits at least one recess reaching back to the indentation. The length of the recess is at least as great as the length of the projection, and seen in the longitudinal direction, the recess and the projection occupy positions that are staggered, one relative to the other.

Abstract: Flooring material including floor boards (1) with an essentially square, rectangular or rhomboidal shape. The floor boards (1) are provided with edges (2), a horizontal lower side (5) and a horizontal decorative upper surface (3). The floor boards (1) are provided lower joining lips (10) at two adjacent edges (2) while the two remaining edges (2) are provided with upper joining lips (20). The lower joining lips (10) are provided essentially vertical lower lip surfaces 911) arranged parallel to the closest edge (2). The lower surfaces (11) are intended to interact with mainly vertical upper lip surfaces (21) arranged on the upper joining lips (20). Two joined adjacent floor boards (1) are hereby locked together in a horizontal direction.

Abstract: A floorboard and an openable locking system therefor comprise an undercut groove on one long side of the floorboard and a projecting tongue on the opposite long side of the floorboard. The undercut groove has a corresponding upwardly directed inner locking surface at a distance from its tip. The tongue and the undercut groove are formed to be brought together and pulled apart by a pivoting motion which has its center close to the intersection between the surface planes and the common joint plane of two adjoining floorboards.

Abstract: The invention relates to a fastening system (1) for rectangular, tabular panels (2, 3, 10), especially floor panels. Comprising retaining profiles disposed on the small faces of said panels (2, 3, 10). Opposite retaining profiles match said retaining profiles in such a manner that similar panels (2, 3, 10) can be interlinked. The panels are provided with opposite first retaining profiles that are configured in such a manner that on a panel (2, 3, 10) being in first line a new panel (2) can be locked in second line by attaching the new panel (2) to the installed panel (3) at a temporary angle relative to the installed panel (3) and then swiveling it down into the plane of the installed panel (3). The panel further comprises opposite second retaining elements that comprise corresponding hook elements (6, 7).

Abstract: The invention concerns a floor covering formed of hard panels (2) which are provided, at least on two opposite edges (3-4, 5-6), with coupling devices (7) made in one piece with the panels (2), whereby these coupling devices (7) provide for an interlocking in a direction (R1) perpendicular to the plane of the floor covering (1), as well as in a direction (R2) perpendicular to the edges (3-4, 5-6) concerned and parallel to the plane of the floor covering (1). These coupling devices (7) comprise a tongue (8) and a groove (9). The lip (11) which is situated on the bottom side of the groove (9) is longer than the lip (10) on the top side. The edge (5) which is provided with the tongue (8) is made elastically flexible.

Abstract: A floorboard and an openable locking system therefor comprise an undercut groove on one long side of the floorboard and a projecting tongue on the opposite long side of the floorboard. The undercut groove has a corresponding upwardly directed inner locking surface at a distance from its tip. The tongue and the undercut groove are formed to be connected by adjoining boards being brought together and snapped together.

Abstract: Floor covering, consisting of floor panels (1) based on a fiber-like material bound by a binding agent, more particularly MDF or HDF, which, at least at their edges, are connected to each other by means of a connection, more particularly a tongue-and-groove connection (2-3) which connection consists of coupling parts which are made in one piece with the floor panels and is shaped in such a manner that the floor panels (1) are locked glue-free in the direction parallel to the plane of the floor covering and transverse to the connection, as well as in a direction perpendicular to this plane, characterized in that, at least at the location where the floor panels (1) cooperate with each other, a sliding agent (12-12A) is provided at least on one of the floor panels (1).

Abstract: A novel structural thermal framing and panel system for assembling finished or unfinished walls with multiple combinations for poured and nonpoured walls comprising of a permanent structural framing stud which can be adjusted to different wall thickness, a plurality of permanent forms, wherein the pluralities of permanent forms are interchangeable with various other permanent panel forms with or without defined spaces for receiving filler, and wherein the framing stud substantially conforms to a portion of the pluralities of panel forms and resists bending in the panel forms. The framing stud is the main structural element in the wall. A structural framing system in combination with insulated panel forms with various defined spaces for receiving filler, and wherein panels may not be prefinished to form a rigid substrate.

Abstract: A tile flooring system composed of modular interlocking tiles. Each modular interlocking tile is adapted to be coupled to another modular interlocking tile. Each tile includes a body having a playing surface, two male interlocking sides, and two female interlocking sides. Each also tile includes an interlocking mechanism coupled to the male interlocking sides and the female interlocking sides. The interlocking mechanism is adapted to allow the modular interlocking tile to be connected to the another modular interlocking tile in a staggered fashion.

Abstract: The invention relates to the articulated imbrication of concrete slabs i(in situ) wherein joints are formed by laying i(in situ), along joint lines, a simple armored mesh device with a cut and fold pattern which has been already prepared in the workshop. Advantage is taken from the retraction phenomenon in order to achieve an alternative indentation along the joints of adjacent slabs of continuous cast concrete, susceptible of forming satisfactorily a knee—or gimbal-joint connection between the joints. The process is complemented with a concrete separator element which facilitates the formation of the crack and prevents water from reaching the platform, and which can be fixed to said device. The invention applies to concrete surface roads, highways and harbour zones of goods warehouses and enables to design and make road surfaces without bases and subbases.

Abstract: A plastic building board preferably used in the building of an outdoor deck has first and second opposite sides which are different in color from one another. The board also has a male connector at one of its side edges and a female connector at the other of its side edges. The male and female connectors are symmetrical to allow connection of the board with another corresponding board with either one of the colored sides in an upwardly facing direction.

Abstract: A storage enclosure including a plurality of panels defines an interior space. At least one of the plurality of panels includes a mounting interface configured to couple an accessory to one of the plurality of panels, and a panel interface configured to couple adjacent panels.

Abstract: The disclosed invention is a portable floor comprised of interlocking floor panels which may be used for dancing, theatrical productions, musical performances, trade shows, and other settings where it is desirable to have a firm wooden floor surface. The disclosed invention enables a single person to install or disassemble the portable floor. It eliminates the need for storing any additional hardware to connect the panels to one another. No special tools are required to assemble or disassemble a floor. The floor is easy to assemble. Once the portable floor is assembled each panel is locked at two different places, thus firmly connecting the floor together. Panels may be added as desired to increase the size of the floor.

Abstract: In a method of laying floor panels having circumferential tongues, receiving grooves, locking grooves and locking lips, a first row of floor panels is joined through interlocking engagement of the shorts sides. The connection of the floor panels of each subsequent row of floor panels is implemented through attachment along their shorts sides as well as attachment of their long sides with the long sides of each preceding row of floor panels, by using wedges by which neighboring floor panels can be reliably pushed together in longitudinal and transverse directions, while at least partially engaging, without play, the locking lips with the locking grooves as well as the tongues in the receiving grooves.

Abstract: Flooring material including floor boards (1) with an essentially square, rectangular or rhomboidal shape. The floor boards (1) are provided with edges (2), a horizontal lower side (5) and a horizontal decorative upper surface (3). The floor boards (1) are provided with lower joining lips (10) at two adjacent edges (2) while the two remaining edges (2) are provided with upper joining lips (20). The lower joining lips (10) are provided essentially vertical lower lip surfaces 911) arranged parallel to the closest edge (2). The lower lip surfaces (11) are intended to interact with mainly vertical upper lip surfaces (21) arranged on the upper joining lips (20). Two joined adjacent floor boards (1) are hereby locked together in a horizontal direction.

Abstract: An interlockable element for a structure assembly set includes an at least partially planar body and a connector edge having associated therewith a first A-type and B-type connector pair disposed about a first axis of rotation and a second A-type and B-type connector pair disposed about a second axis of rotation. The first and second axes of rotation are disposed on opposing sides of a generally rectangular quadrilateral of a specified dimension. Each of one pair of diagonally opposite vertices of the quadrilateral are situated internally to each of the A-type connectors and each of the other pair of diagonally opposite vertices of the quadrilateral are situated internally to each of the B-type connectors; and the quadrilateral is generally disposed in a plane that is generally perpendicular to the plane of the body of the interlockable element. The A-type connectors are interlockable with the B-type connectors.

Abstract: A wallboard, wallboard joint and method for joining adjacent wallboards. A first wallboard has first and second edges extending between a face and back of a core. The second edge is an inverted mirror image of the first edge. A facing-material covers the face and has a first end extendable beyond the face. The first end has an adhesive surface covered by a removable strip. The wallboard joint and method for joining adjacent wallboards provides for overlapping and mating the first edge of the first wallboard with a second edge of a substantially similar second wallboard, securing the first and second wallboards to a structural member by passing a fastener through the first and second edges and into the structural member, and adhering the adhesive surface of the face of the first wallboard to the second wallboard.

Abstract: A panel, particularly a floor-covering panel, is provided that has separate horizontal and vertical locking structures. The panel has a first side edge and a second side edge. The first side edge has a groove and a locking lip, and the second side edge has a tongue and a locking tongue. The first side edge of one panel interlocks with the second side edge of another panel without adhesives or fasteners such that the tongue and groove form a joint that provides a vertical interconnection lock and the locking lip and locking tongue form a joint that provides a horizontal interconnection lock. Advantageously, one or more first side edge surfaces opposite surfaces of the second edge locking tongue have a space between them. The separate horizontal and vertical locking structures reduces, if not prevents, damage to the locking structures during joining of panels.

Abstract: A flooring panel or wall panel (20) is provided with a tongue (1) and a groove (2) each comprising cooperating locking means in the form of ribs (11, 12) and grooves (9, 10). The locking means of the upper side and lower side of the tongue (1) and groove (2) respectively are arranged staggered in an insertion direction in which the two panels to be joined to each other are joined to configure a firm joint between two adjoining panels at which an additional surface portion (31; 32; 51) step (31) is provided at the surface area of the upper cheek (3) facing the groove (2) and/or of the lower cheek (5) of the groove which is formed as a step (31) or bevel (32: 51).

Abstract: A building panel, such as a flooring panel or wall panel and a method of assembling the same into a floor, wall cladding, etc. The panel is provided with a locking means in the form of groove (6) and tongue (7) forming a tongue/groove joint for assembling of the panels. In a preferred embodiment, the groove (6) and the tongue (7) are made of water resistant material and formed with a snap-together joint.

Abstract: A floor pad module is formed along its four edges with specially designed first and second dovetails and corresponding dovetail grooves, so that the floor pad module could be reversed without affecting its free connection to another floor pad module via engagement of the dovetails with the dovetail grooves. This enables the floor pad module to be manufactured with two different colors shown at a front and a reverse side thereof, and a consumer may connect a plurality of the floor pad modules to form a large area of floor pad showing differently colored patterns simply by reversing some of the floor pad modules in the same one pack without the need of purchasing two or more packs of monochromatic floor pad modules.

Abstract: A flooring member comprising a top, a bottom, a first edge, a second edge, a tongue member configured to be received within a groove member of an adjacent flooring member, the tongue member extending generally perpendicular from the first edge and having a top surface and a bottom surface, the tongue member top surface is inclined away from the flooring member top at a first angle, the tongue member bottom surface is inclined toward said flooring member top at a second angle, the second angle being less than the first angle so that a gap resistant interconnection of the tongue within a groove of an adjacent flooring member is achieved.

Abstract: A system for modular construction provided by interconnectable and stackable polymeric blocks having end and side walls connected to a top wall, and exterior and interior cylinders. The exterior cylinders are matable with the interior cylinders of a connecting block, and apertures in the top wall allow for re-bar, conduit or installation of insulation. Raised ribs located adjacent to the top wall contact the connecting block to further enhance stability of the erected structure.

Abstract: Blocks with internal capsules having superior thermal resistance, solar control qualities, projectile-resistant properties and/or sound-dampening properties are described. The blocks are comprised of a structural exterior that encompasses a capsule. The capsule may be segmented into chambers with dividers. The capsules may be designed to provide various benefits including, but not limited to, improved insulating characteristics, increased projectile resistance, and/or a range of visual, thermal and strength characteristics. Various types of blocks with internal capsules and assembled panels of block with internal capsules are disclosed, along with methods of manufacturing and use of the blocks and panels.

Abstract: A block assembly for constructing a seawall and dissipating waves. The block assembly includes a block comprising a front wall, a left side part and a right side part. The left and right side parts include stepped surfaces and a plurality of round shaped projection parts are closely disposed on the front wall. The block further includes two connecting walls having male protrusions and female recesses formed on upper and lower surfaces thereof.

Abstract: An improved waterproofing system for the concrete slab of a flat roof on a building is disclosed. The waterproofing system uses hollow plastic panels of designed size, different thickness, and groove and tongue joints for interconnecting the panels. A supplementary waterproofing layer may be installed using sheet membrane materials such as asphalt sheet, metal sheet and other sheets on vertical surfaces, especially the parapet of the roof. The invention further concerns a construction method for applying a fiber mesh reinforcement on the connection joint and for applying fluid-applied materials on the substrate with sheet membrane layers on vertical surfaces. The waterproofing layer of sloped step type, hollow plastic panels of different thickness, permits fast drainage of stagnant water, which inhibits weather damage to the waterproofing layer.

Abstract: A wall block arranged to be stacked vertically for creation of a retaining wall, the block being of generally trapezoidal configuration having parallelly arranged front and rear surfaces along with opposed top and bottom surfaces. The top surface has front and rear lips formed thereon with each of the lips having a trapezoidal root portion with mutually opposed triangular portions converging inwardly therefrom to define opposed and aligned front and rear apices. In one embodiment, the apices are disposed midway along the length of the block, while in a second embodiment, the apices are formed at the juncture point of mated pairs of blocks. The bottom surface of the block includes a central base with opposed notches formed along the front and rear edges of the bottom surface, with the base having a trapezoidal configuration with a width dimension which is no greater than the spacing between the opposed aligned front and rear apices.

Abstract: Floor panels and floor elements therefore are made of sheet-shaped cores which before application of the surface of the floor panels are formed with sealing means for counteracting changes in the properties of the floor panels caused by moisture.

Abstract: A block for use in interlocking with other similar blocks in constructing a building has a block body having a top surface and a bottom surface with an outer block wall defining one side surface of the block body. A head portion extends from the outer block wall toward an opposed side surface. A connecting portion on respective sides of the head arranged to receive at least one correspondingly shaped connection portion of at least one second block in interlocking relationship therewith. Two abutment portions are arranged each at a respective end of the outer block wall and each defining a respective abutment shoulder.

Abstract: A tile flooring system composed of modular interlocking tiles. Each modular interlocking tile is adapted to be coupled to another modular interlocking tile. Each tile includes a body having a playing surface, two male interlocking sides, and two female interlocking sides. Each also tile includes an interlocking mechanism coupled to the male interlocking sides and the female interlocking sides. The interlocking mechanism is adapted to allow the modular interlocking tile to be connected to the another modular interlocking tile in a staggered fashion.

Abstract: A prefabricated room module (1) is provided for use in the construction of a modular building. The room module comprises a floor slab (2) of generally rectangular shape in plan, and load bearing walls (3,4) formed at adjacent sides of the slab and mutually adjoining at a common corner (5). The module has no ceiling slab opposite the floor slab (2) and an open face opposite one of the load bearing walls (4) which constitutes a party wall. Opposite another of the load bearing walls (3) the module may be open or include a further wall (7) which can have an access opening (10) therein for providing service access to a kitchen or bathroom pod (9) installed in a corner of the module. Edges of the floor slab (2) have projecting tongues (11) and fastening means for engaging complementary recesses and fastening means respectively of an adjacent module. The module may have a ceiling slab instead of a floor slab (2).

Abstract: The invention relates to flat and/or elongated building components (1, 2), preferably wooden, and a structure connecting these components (1, 2) in accordance with the groove and tongue principle. Two legs (3, 4) forming a groove (5) branch off from a front face of one of the components (1), and a tongue (6) branching off from a front face of the other component (2) can be inserted into the groove (5). Locking elements (7, 8) hold the components (1, 2) in an assembled position. In accordance with the invention, the locking elements are configured as triangular projections (7) and cavities (8) in facing or adjacent surfaces of the groove and/or tongue.

Abstract: The present invention relates generally to a building construction system, the components thereof, and method therefore. More specifically, the present invention relates to a building construction system that utilizes specifically designed component parts that fit together, such as by male/female connections, and are permanently attached through the use of an adhesive, or bonding glue, to create an extra strong and uniformly tight structure. If effect, the end result is equivalent to a one-piece construction since all components are permanently “chemically welded” to each other with all components being made from the same type of materials.

Abstract: A building panel, such as a flooring panel or wall panel and a method of assembling the same into a floor, wall cladding, etc. The panel is provided with a locking means in the form of groove (6) and tongue (7) forming a tongue/groove joint for assembling of the panels. In a preferred embodiment, the groove (6) and the tongue (7) are made of water resistant material and formed with a snap-together joint.

Abstract: A building panel, such as a flooring panel or wall panel and a method of assembling the same into a floor, wall cladding, etc. The panel is provided with a locking means in the form of groove (6) and tongue (7) forming a tongue/groove joint for assembling of the panels. In a preferred embodiment, the groove (6) and the tongue (7) are made of water resistant material and formed with a snap-together joint.