Abstract: A swim device comprising elongated foot pockets which surround each of the feet of the swimmer, continued distally with tapers ending in neckings connected in a functional manner to blades for each foot. The neckings of the tapers of both feet may be connected to one blade (monofin). A swim device comprising a cowling of generally elongated shape which surrounds both feet of the swimmer, continued distally with a taper, ending in a necking to which one blade (monofin) is connected in a functional manner. The tapers and the hydrodynamic cross-sections of the foot pockets and of the cowling, result in stronger thrust and lower drag than in the designs of prior art.

Abstract: A combined diving utensil has a buckling assembly, a seesaw and a fastening element. The buckling assembly includes a male buckle and a female buckle. Of which, one end of the female buckle is provided with an opening, and the other end provided with a mating joint. One end of the male buckle is provided with a threading portion, and the other end provided with an extension coupled with the mating joint. A plurality of ribs are set on one surface of the fastening element, which is set on the threading portion of the male buckle. A stopper is set close to the end of the fastening element. The seesaw is provided with a thrust rib plate, which is mated with a plurality of ribs on the fastening element and pivoted on the female buckle via the fulcrum.

Abstract: An aquatic exercise device (100) includes a cuff strap (102) for fastening a plurality of fins (106) to a user's leg. The cuff strap (102) is configured to position the plurality of fins (102) to extend outwardly form an interior of the cuff strap (102) when the cuff strap (102) is fastened to an ankle area of the user's leg. The plurality of fins (106) provide resistance in a direction opposite to the direction of motion of the user's foot when the aquatic exercise device (100) is moved through water.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: A swimming device for a swimmer or diver is described, which has a monofin, a power transfer element for moving the monofin using muscle power, and a fastening device for fastening the power transfer element to the lower legs of the swimmer. The power transfer element has a lower leg section, a foot section, and a fin section. In order to achieve the highest possible propulsion in the water with the lowest possible use of force, the power transfer element flows dynamically, in cross section in the X-Z level with a longer Z axis and short X-axis.

Abstract: A swim fin having, in combination, a blade including an inner thin board, and upper and lower Neoprene sheet or sheets covering upper and lower sides of the board, the upper Neoprene sheet defining a foot entrance, a forward foot retention strap or straps carried by the blade to extend proximate said entrance and over the foot, a rearward ankle/heel retainer carried by the blade to extend above the rearwardmost portion of the blade, the forward retention strap and said rearward retainer both being flexible, and primary seam binding extending at the periphery of said board, connecting the Neoprene sheet or sheets to the board and also anchoring the forward strap and the rearward retainer to the board.

Abstract: A swim fin having, in combination, a blade including an inner thin board, and upper and lower Neoprene sheet or sheets covering upper and lower sides of the board, the upper Neoprene sheet defining a foot entrance, a forward foot retention strap or straps carried by the blade to extend proximate said entrance and over the foot, a rearward ankle/heel retainer carried by the blade to extend above the rearwardmost portion of the blade, the forward retention strap and said rearward retainer both being flexible, and primary seam binding extending at the periphery of said board, connecting the Neoprene sheet or sheets to the board and also anchoring the forward strap and the rearward retainer to the board.

Abstract: An aquatic accessory adapted for frictional attachment with a shoe being worn by a user comprises a receptacle portion and a fin portion extending outwardly from the receptacle portion. The receptacle portion is adapted to receive at least a portion of an inserted shoe, and frictionally attach with the shoe. Gripping members can be configured and angled in a manner for providing increased frictional attachment between the aquatic accessory and inserted shoe. The accessory can be fabricated from a stretchable material to provide a radial attachment force for enhancing frictional attachment between the aquatic accessory and an inserted shoe.

Abstract: A snowboard or other glide board has a receptacle and plug accessory system for quickly incorporating additional and interchangeable functionality to the board. A user can readily switch functionality in and out of the board by way of the plug and receptacle system. Various plugs contain different features. The receptacle can be incorporated during manufacturing, such as in a manner compatible with existing manufacturing practices, as a retrofit to existing boards. The receptacle is a plate embedded into the board, in line with the core and sandwiched between the strength layers that are typically comprised of fiberglass. The receptacle sidewall has a one side of a latch mechanism in its interior walls. In one implementation, the plug accessory can latch fit into the receptacle. The plug can be disengaged with one hand without tools. The plug accessory can incorporate a camera, a light, a flag, and a rooster tail duct.

Abstract: Apparatus, devices and methods of operating multiple high aspect ratio hydrodynamic horizontal ladder oriented vanes with pliable hinges and rotation limiting flexible webs attached between flexible support beams on swim fins. The fins can have a foot pocket. A pair of parallel support beams can be secured to the foot pocket and support a plurality of hydrofoil vanes in a resisted pivotal arrangement. Pivotal rotation of the vanes can be restricted by flexible membranes, between vanes and beams, to provide an optimum angle of attack for the during swimming. The fins can have at least one pivoting vane region connected to the fin with a flexible hinge member.

Abstract: The present invention is generally directed to a swim fin generally including a fin blade and a bootie, the bootie including a foot pocket configured to receive a user's foot and ankle, the foot pocket attached to the top surface of the fin blade; and a strap system including one or more straps pulling the user's foot and ankle into the foot pocket toward the distal edge of the fin blade and down against a top surface of the fin blade. Some aspects of the present invention may also include a foot pocket formed from a first portion having a first elastic characteristic connected to the top surface of the fin blade; and a second portion having a second elastic characteristic portion disposed at least on a portion of the top surface of the foot pocket, the second elastic characteristic being greater than the first elastic characteristic.

Abstract: A first flipper has a base, a deformable fin connected to the base, and a first spreader that imposes a first force on the fin that causes the fin to spread in response to relative movement between the first spreader and the fin caused by a first longitudinal deflection of the fin relative to the base. A second flipper has a fin and a foot coupling portion connectable to a foot holding portion of a boot to couple a foot in the foot holding portion to the flipper. A first system includes the flipper and the boot. Methods of using the flippers, the boot, and the system are also disclosed.

Abstract: An adjustable fin apparatus adjustable between a first expanded position including a pair of inner elongated blades 12 and a pair of outer elongated blades 14; the blades 12, 14 are mounted to a blade housing portion 16 comprising an upper housing element 18 and a lower housing element 20; the lower blade housing element 20 comprises an elongate shape having a slot 22 formed therein along a portion of the length of the lower blade housing element 20; the inner elongated blades 12 comprise an inner edge 26 and an outer edge 28 and a bore 30 is located at an end thereof; an outer elongated blade 14 defines an inner edge 32 and an outer edge 34; and the upper blade housing element 18 comprises an elongate shape generally corresponding to the elongate shape of the lower blade housing element 20.

Abstract: A diving fin system possessing two independent subunits, a fin subunit and a shoe subunit. The two subunits are reversibly fastened through a mechanism whereby the fin subunit possesses a front fin clip and a back locking clip, and the shoe subunit possesses a front receiver for the front fin clip and a back locking pin to cooperatively engage the back locking clip of the fin.

Abstract: A fin comprising a foot pocket, two ribs and a web portion is provided in this invention. The foot pocket has a surrounding portion and a base portion, which together define a foot receiving space. The surrounding portion has a plurality of first and second structures; the ribs extend forwards from two sides of the foot pocket respectively; and the web portion is formed between the two ribs. The first structures and the second structures are alternately arranged, and a first thickness of each of the first structures is thicker than a second thickness of each of the second structures. Thereby, the foot pocket of the fin is made flexible and elastic for swimmers or divers with different foot forms and sizes.

Abstract: A fin includes a blade and a foot pocket mounted on a front end of the blade. The blade includes a rubber layer having two opposite sides, and two carbon fiber units mounted on the two opposite sides of the rubber layer respectively. The rubber layer is provided between the two carbon fiber units so as to enhance the elastic coefficient of the blade so that the blade has greater elasticity and flexibility. Thus, when the blade is worn by a user who is swimming or diving in the water, the blade can be flexed and deflected to respond to the moving direction of the water current so as to decrease the drag applied on the blade so that the blade is moved in the water easily, thereby greatly saving the user's energy.

Abstract: A shoe assembly with a retractable fin assembly that moves between two extreme positions. One of the positions is the retracted position with the fin assembly housed within a longitudinally and transversely extending cavity along the shoe's sole. The other extreme position for the fin assembly being distended outside the sole for maximum propulsion use in a body of water. Resilient support members are mounted to the lateral sides of connecting flexible web portions. A releasable fastening mechanism with a stopper for the smallest support member causes the web portions to stay taut.

Abstract: The Reverse Thrust Flipper is a swimming flipper similar to a regular swimming (scuba diving, exercise, recreational) flipper that has the function of generating thrust in the opposite direction to the swimmers direction. The purpose of this flipper is to allow the swimmer to exercise without the need of a large body of water. The flipper's reverse thrust reduces de forward movement while still requiring the swimmer to exert the same amount of work. Its oscillating fin makes it possible to produce the reverse thrust in both the upward and downward leg strokes, thus maximizing the work out and enabling a simulated forward swimming experience.

Abstract: Swimming fins of the kind comprising a foot pocket provided with a outsole and an upper closed at the tip and open at the heel zone, for lodging with slight clearance the feet of a scuba diver wearing diving booths, characterized by the fact that the outsole and/or the upper sections of the said fins are provided with a number of through holes.

Abstract: A swim fin includes a foot cover, a fin blade, and a pair of reinforcement ribs extending from two sides of the foot cover. The fin blade is disposed between the pair of the reinforcement ribs and fixedly connected to the pair of the reinforcement ribs. Each reinforcement rib includes a front rib portion, a middle rib portion, and a rear rib portion. The rear rib portion has a bottom fixedly connected to the foot cover. The middle rib portion has at least a cavity extending axially and a spring in the cavity to improve the resilience of the reinforcement rib. The spring has two ends connected to the front rib portion and the rear rib portion, respectively. The one spring or the plurality of springs in the reinforcement rib of the present invention is to replace a conventional solid reinforcement rib, with the property of the spring.

Abstract: Apparatus, devices and methods of using and operating multiple high aspect ratio hydrodynamic horizontal ladder oriented vanes with pliable hinges and rotation limiting flexible webs that are attached between flexible support beams on swim fins. The fins can have a foot pocket for attaching to a swimmer or diver's foot. A pair of roughly parallel support beams can be secured to the foot and toe portion of the foot pocket and support a plurality of hydrofoil vanes therebetween in a resisted pivotal arrangement. Pivotal rotation of the hydrofoil vanes can be restricted by flexible membranes, between the hydrofoil vanes and the support beams, to provide an optimum angle of attack for the hydrofoil vanes during a swimming stroke. Methods for increasing lift and decreasing turbulence and drag on hydrofoils and swim fins part of the fins.

Abstract: Heel strap (5) for swimming flippers (1) of the open shoe type (3), comprising a tubular resilient element (10), with a round cross section, connected to each end and connected removably to means (12, 11) for supporting a rigid eyelet (9) which can be attached removably to a corresponding pivot pin (6, 7) projecting laterally from the flipper (1).

Abstract: A swim fin boot includes a fin portion having a body member and a pair of opposed side rails, each side rail including an extension segment connected to a proximal end of the body member and extending away therefrom, respective extension segments being spaced apart from and parallel to one another. Each side rail includes a boundary segment connected to body portion peripheral edges, the body portion extending between the side rail boundary segments. A boot member includes an ankle portion defining an open top configured to selectively receive insertion of a person's foot. The boot member includes a foot portion connected to a lower end of the ankle portion defining an interior cavity configured to receive the person's foot when inserted into the ankle portion, the foot portion being connected to respective side rail extension segments such that the fin portion and the boot member have a unitary construction.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: A flipper for swimming or underwater activities or muscular training, includes a blade and a shoe, the ends of which facing one another are dynamically and kinematically separate. The blade has extensions projecting backwardly and fixed to the shoe in areas substantially corresponding to its central part. Elastic tier rods are provided between the blade and the front part of the shoe and are designed to control angular variations between the blade and the shoe.

Abstract: Apparatus and methods for body surfing which provide the body surfer a means to stabilize his ride and control his direction/position on a wave are described herein. According to one aspect, a body surfing apparatus includes a body suit having a torso and legs; a plurality of fins located on the torso; and one or more fins located laterally on the legs. The fins are preferably attached to the body suit via an adhesive or mechanical means and the fins and suit are preferably covered with a buoyant layer, the buoyant layer having a minimum thickness of 1 mm.

Abstract: The invention relates to a flipper comprising a bootee extended to the front by a flexible wing section, at least one flexible element placed in the direction of the length under the flexible wing section and securing means arranged between the proximal part of the flexible element and the proximal part of the flexible wing section.

Abstract: Disclosed herein are apparatus and methods for enhancing swimming and facilitating walking on land. In some embodiments, the apparatus includes a foot thong having a body and a toe tether. The apparatus can include a swim fin device having a sole portion, toe portion, and fin portion, wherein the sole portion and toe portion cooperate to define an opening for receiving the toe tether to secure the swim fin device to the foot thong. Additionally disclosed herein is a recreational swimming ensemble comprising the swim fin device(s), the swimming glove(s), and/or a mask configured to be secured to goggles, wherein a common theme can be distributed across the swim fin device, swimming glove, and mask.

Abstract: A swimming fin comprising a blade extending from a shoe open at its rear side, and a rear heel strap connected to the sides of the shoe by at least one buckle, the buckle having a base plate integral with the shoe. A buckle arm is joined with the strap so as to allow adjustment of the strap's tension, an intermediate lever being connected pivotally to the base plate and the arm. A reversible attachment member is also provided for connecting the intermediate lever to the base plate to achieve closure of the buckle. Between the intermediate lever and the base plate, a disengageable articulation member is provided for reciprocal engagement between them, a pivotal connection, and, at the same time, for allowing their separation in a direction opposite to that of tensioning the strap. In this manner, the intermediate lever may be separated from the base plate following release of the attachment member, and disconnection of the disengageable articulation member.

Abstract: A swimming shoe includes a shoe unit comprising two spaced hook members pivotably formed on either side, each of the hook members including a projection on one surface facing either a heel portion of the shoe unit or a toe portion thereof; and two side boards hingedly secured to both sides of the shoe unit respectively, each of the side boards comprising two spaced rectangular through holes each shaped in conformity to the adjacent hook member. Ends of the hook members are directly above the through holes. Thereafter, upward pivoting the side boards to pass the hook members through the through holes will cause inner surfaces of the through holes to be lockingly urged by the projections. The ends of the hook members are adapted to dispose in a position besides the through holes by pivoting.

Abstract: Methods are disclosed to design resilient hydrofoils (164) which are capable of having substantially similar large scale blade deflections under significantly varying loads. The methods permit the hydrofoil (164) to experience significantly large-scale deflections to a significantly reduced angle of attack under a relatively light load while avoiding excessive degrees of deflection under increased loading conditions. A predetermined compression range on the lee portion of said hydrofoil (164) permits the hydrofoil (164) to deflect to a predetermined reduced angle of attack with significantly low bending resistance.

Abstract: Disclosed herein are apparatus and methods for enhancing swimming and facilitating walking on land. In some embodiments, the apparatus includes a foot thong having a body and a toe tether. The apparatus can include a swim fin device having a sole portion, toe portion, and fin portion, wherein the sole portion and toe portion cooperate to define an opening for receiving the toe tether to secure the swim fin device to the foot thong.

Abstract: An adjustable fin apparatus includes an elongated blade portion and elongated first and second frame members adapted for pivotal connection to the blade. An adjustment system for the first and second frame members rotates the pivotal connection of the frame members with respect to the blade. A thin web of a flexible polymeric material extends between the first frame member and the blade portion and between the second frame member and the blade portion.

Abstract: An amphibious shoe has a sole with a fin compartment integrated therein retractably houses of a lightweight fin that converts the shoe from a walking shoe to a swimming shoe. The amphibious shoe includes a fin comprising ridges intermittent between material arranged in an accordion construction. The fin is capable of being ejected from the compartment and expanded to a fan configuration. The shoe is further provided with a pivotal stabilizing strap for enhanced stability during swimming. In one embodiment the fin is removed by a release button in communication with a spring. Other embodiments provide for manual deployment by pulling on the fin from the fin compartment. In operation, the wearer can comfortably run or walk swiftly along the land as the integrated fin has a thin lightweight construction. Upon reaching the water's edge, the shoe is readily converted for swimming by ejecting and positioning the fin.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: A swim fin includes a foot cover, a fin blade, and a pair of reinforcement ribs extending from two sides of the foot cover. The fin blade is disposed between the pair of the reinforcement ribs and fixedly connected to the pair of the reinforcement ribs. Each reinforcement rib includes a front rib portion, a middle rib portion, and a rear rib portion. The rear rib portion has a bottom fixedly connected to the foot cover. The middle rib portion has at least a cavity extending axially and a spring in the cavity to improve the resilience of the reinforcement rib. The spring has two ends connected to the front rib portion and the rear rib portion, respectively. The one spring or the plurality of springs in the reinforcement rib of the present invention is to replace a conventional solid reinforcement rib, with the property of the spring to improve the resilience of the reinforcement rib.

Abstract: Swimming flipper comprising a shoe part from which two ribs extend laterally, and a fin part, characterised in that said fin part is connected at one end to said shoe part, while its other end is constrained to said ribs in the vicinity of their ends, the sides of said fin part being at least partly not constrained in any way to the said side ribs, all of which so that during the active and passive phases of the flipper movement the free part and the constrained part of the said fin bend in the opposite directions forming substantially an S shape.

Abstract: A strap with tapered-apertures for open-heeled swim fins is stretched from a first end connection to a conventional boss-button and boss-post structure, whereby the strap will apply a desired level of force as a holding-pressure against the heel of a swimmer. The strap's tapered-apertures are cast to link the tapered dimensions of aperture walls to an easy passage of the strap over the boss button and to a highly resistant passage of the strap-top to a designed seat against the top's raised arches. The manufactured formation of the unique aperture shapes result in an unexpected elasticity of the strap. The combination of aperture structure within the raised arches guide the orifice walls of the aperture into compression, instead of tension, greatly resisting forces to release the strap from the boss-posts and buttons.

Abstract: An amphibious shoe has a sole with a fin compartment integrated therein retractably houses of a lightweight fin that converts the shoe from a walking shoe to a swimming shoe. The amphibious shoe includes a fin comprising ridges intermittent between material arranged in an accordion construction. The fin is capable of being ejected from the compartment and expanded to a fan configuration. The shoe is further provided with a pivotal stabilizing strap for enhanced stability during swimming. In one embodiment the fin is removed by a release button in communication with a spring. Other embodiments provide for manual deployment by pulling on the fin from the fin compartment. In operation, the wearer can comfortably run or walk swiftly along the land as the integrated fin has a thin lightweight construction. Upon reaching the water's edge, the shoe is readily converted for swimming by ejecting and positioning the fin.

Abstract: A swim fin includes a foot pocket and a blade portion. The blade portion includes a top surface and a bottom surface. An opening is disposed through the blade portion to permit an enhanced directional fluid flow between the top and the bottom surface. A top bevel is disposed in the top surface and surrounds the opening. The top bevel includes a trailing and a leading top bevel area to compress the fluid flow.

Abstract: An amphibious shoe has a sole with a fin compartment therein. The fin compartment provides retractable housing for a lightweight fin for conversion from a walking to swimming shoe. In one embodiment the amphibious shoe includes a fin comprising a plurality of ridges. The ridges are intermittently disposed between material arranged in an accordion construction. When ejected from the compartment, the ridged material expands to a fan configuration. The fan is further appointed with a pivotal stabilizing strap for enhanced stability during swimming. In another embodiment the amphibious shoe includes at least two fin plates pivotally attached about an axis. The fin plates are stowed in an overlapping condition. They are capable of being ejected from the compartment and opposingly rotated toward the front of the shoe abutting to form a swim fin. In operation, the wearer can comfortably run or walk swiftly along the land as the integrated fin has a thin lightweight construction.

Abstract: Disclosed herein are apparatus and methods for enhancing swimming and facilitating walking on land. In some embodiments, the apparatus includes a foot thong having a body and a toe tether. The apparatus can include a swim fin device having a sole portion, toe portion, and fin portion, wherein the sole portion and toe portion cooperate to define an opening for receiving the toe tether to secure the swim fin device to the foot thong.

Abstract: A swim fin that changes down kick force is revealed. The swim fin worn over the foot to aid movement through the water includes a footpocket and a flat fin blade. The flat fin blade extends from the front part of the footpocket and has an upper blade surface and a lower blade surface. At least one blade surface is disposed with two fin ribs arranged symmetrically. By being embedded with heavy objects inside the fin rib, the weight of the swim fin is increased so as to increase the force of the swim fin acted on the water by kicking. This favors down kick of legs and the propelling force of kick is increased so that the user is allowed to move faster in the water with the swim fin.

Abstract: Swim fins that attach to the legs of a swimmer to aid movement through the water. In one example embodiment, a swim fin includes an upper support frame, a lower support frame, a lower blade attached to the lower support frame, and at least one hinge assembly connecting the upper support frame to the lower support frame. The upper support is configured to be generally positioned along and attached to the front of a swimmer's lower leg between the swimmer's knee and ankle The lower support frame is configured to extend, in a swimming position, from a position proximate the swimmer's ankle to a position beyond the end of the swimmer's foot. The at least one hinge assembly allows the lower support frame to be rotated upward from the swimming position to a walking position. The walking position enables the swimmer to walk barefoot on a surface without the lower support frame nor the lower blade substantially contacting the surface.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: A swim or diving fin includes a footpocket for housing a foot, a blade extending from the front end of the footpocket member, a frame member extending for at least a portion of the blade. The frame member or members includes a closed loop perimetric rim member having two opposite longitudinal branches delimiting an inner hollow region and also having one or more transversal bridges connecting the longitudinal branches. The blade is connected to the frame member at one or more of the transversal bridges and/or at least at one or more ends of the rim member.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: Swimming fins of the kind comprising a foot pocket provided with a outsole and an upper closed at the tip and open at the heel zone, for lodging with slight clearance the feet of a scuba diver wearing diving booths, characterised by the fact that the outsole and/or the upper sections of the said fins are provided with a number of through holes.

Abstract: A flipper for swimming or underwater activities or muscular training, includes a blade and a shoe, the ends of which facing one another are dynamically and kinematically separate. The blade has extensions projecting backwardly and fixed to the shoe in areas substantially corresponding to its central part. Elastic tier rods are provided between the blade and the front part of the shoe and are designed to control angular variations between the blade and the shoe.

Abstract: A swim fin includes a foot pocket and a blade portion. The blade portion includes a top surface and a bottom surface. An opening is disposed through the blade portion to permit an enhanced directional fluid flow between the top and the bottom surface. A top bevel is disposed in the top surface and surrounds the opening. The top bevel includes a trailing and a leading top bevel area to compress the fluid flow.