Abstract: The present invention provides a multifunctional fitness frame with a reversible pedal structure, which comprises a main frame, a pull ring arranged on the main frame and a pedal arranged on the main frame, wherein the pedal is arranged on the main frame in a reversible manner, and a support tube and a rotating shaft are also penetrated on the main frame; the pedal is turned over by the rotating shaft and leans against the support tube to facilitate the user to practice paddling; and the pedal can also be turned over and leaned against the ground by the rotating shaft to realize storage, so that the user can practice other actions conveniently.

Abstract: A core exercise apparatus having a frame. The frame has a first wall, a second wall, a frame roof, and a frame floor. A first bumper is coupled to the frame roof. A second bumper is coupled to the frame roof. A first plate is coupled to the first frame wall. A second plate is coupled to the second frame wall. An elongated handle is coupled to the frame floor. A pendulum is coupled to the first plate and second plate such that the pendulum swings from the first bumper to the second bumper and from the second bumper to the first bumper.

Abstract: An upper posterior development device is shown and described. The upper posterior development device includes a frame. The frame is created by a plurality of legs. The legs may be secured to one another at a bottom end for additional support. A bench is secured to the upper end of at least one of the plurality of legs. The bench may be rotatably secured to the frame such that the angle of the bench is adjustable. In this instance the bench is secured at least one different leg of the plurality of legs via an adjustment device. A pendulum movably secured to an underside of the bench. The pendulum is configured to have weight added or removed therefrom.

Abstract: An exercise apparatus for attachment to an exercise rack including an arm, including: at least one mounting prong connected to the arm; and, a stand including a pivot point, wherein the pivot point defines a pivot axis substantially transverse to a longitudinal axis of the arm, and wherein the stand is configured in a first, vertical configuration when the apparatus is at rest and a second, largely horizontal configuration when the apparatus is in motion, and wherein the stand is rotatable with respect to the arm about the pivot axis to transition the stand from the first configuration to the second configuration.

Abstract: A piece of exercise equipment particularly for improved strength training exercises. More particularly, the invention relates to equipment that allows the user to vary tension when performing different exercises. The present invention is specifically designed for improved exercise through the variability of a tension component for use in such exercises as the plank exercise, sit-ups, push-ups and supine pull-ups that includes a core support, a guide arm, a head support, and a foot support that work in conjunction to most optimally support the user. The core support, the head support and the foot support are all connected, supported, and elevated from the floor by a central support system.

Abstract: The present disclosure provides training systems and apparatus for working out. The training system includes a pivotal bracket and a workout bar. The pivotal bracket includes a first portion and a second portion pivotally coupled to the first portion. The first portion is couplable to a support surface. The workout bar is coupled to the second portion of the pivotal bracket. The workout bar includes a cylindrical weight receiving portion positioned distal relative to the second portion of the pivotal bracket and a rectangular intermediate portion positioned between the second portion of the pivotal bracket and the cylindrical weight receiving portion. The weight bar may include a plurality of pairs of holes spaced apart along a length of the bar for receiving various attachment members for performing landmine workout movements. The training system may include other support structures to which the pivotal bracket is connected.

Abstract: A weightlifting exercising system includes a frame having a pair of columns. A pair of lifting assemblies is provided and each of the columns has one of the lifting assemblies mounted thereon. The lifting assemblies each include a mount and an axle extending through the mount and rotational relative to the mount. A first arm is fixedly attached to the axle. A second arm is rotationally coupled to the axle. A lift angle is defined between the first and second arms and is alterable from 0° to 180°. A locking member releasably locks the second arm with respect to the axle such that the lift angle is releasably retained. One of the first and second arms has a handle attached thereto and the other of the first and second arms has a weight receiver attached thereto. One or more weight plates is removably positionable on the weight receiver.

Abstract: Described is a machine for assisted physical activity exercise, comprising a base (4) and supporting means (2, 3) for a user, comprising a seat (3) and/or a backrest (2). The assisted physical activity exercise machine (1) comprises a training tool (6) mounted on the base (4). The training tool comprises an engagement portion (7), configured for being actuated by a user, and guiding means (8) associated with the engagement portion (7) for guiding it at least according to a lifting movement. The supporting means (2, 3) are mounted on the base (4) and comprise a slide (100) slidably mounted on the base (4) according to an adjustment movement. The slide (100) supports the seat (3) and/or the backrest (2).

Abstract: A knee extension training device is provided with knee abutment rolls, heel abutment rolls and feet anchor rolls to facilitate a user from standing on the device in an upright manner with the knees, the heels, and the feet abutting the respective abutment rolls such that knee extension stretching and flexion exercise can be carried out by utilizing the user's own body weight.

Abstract: An exercise attachment apparatus for attachment to a lever arm pivotably connected to an exercise rack, including at least one mounting prong connected to the lever arm; and, a stand including a pivot point, wherein the pivot point defines a pivot axis substantially transverse to a longitudinal axis of the lever arm, and wherein the stand is rotatable with respect to the lever arm about the pivot axis.

Abstract: Apparatus, systems, and methods for executing a “tire flip” weight lifting exercise. The disclosed apparatus includes a chassis and a tire assembly that is lifted and flipped during the exercise. The tire assembly includes a support bar that extends through a tire. The tire assembly also includes bearing assemblies that engage arms of a torsion bar that is pivotable with respect to the chassis to provide for safe and controlled movement of the tire assembly during the lifting exercise. When the lift is completed, rollers engage the tire assembly so that the tire assembly can roll back to the starting position at least in part due to the force of gravity.

Abstract: A weight training sled (100) characterized by one or more of (A) rotatable wheels (130) in contact with ground, (B) curvilinear push handles (140) with comfortably spaced, and inwardly and/or downwardly angled hand grips (143), and (C) an elevated tow hook (160).

Abstract: A weighted pivot arm apparatus attached to a weight rack component, comprising: a body having an upper end and a lower end and extending along longitudinal axis; an attachment point disposed on the body comprising at least one wing with a hole therethrough and wherein the attachment point is rotatably mounted to the weight rack component; and, an impact bumper disposed on a lower end of the body.

Abstract: A weight training apparatus is configured to improve use and enjoyment of free-weights. The apparatus may leverage a modular or changeable assembly to accommodate different exercise or types of free-weight devices. The assembly may include a frame that can accommodate retainers that can secure to both a standard barbell shaft or receive plate weights. The retainers may also accommodate a handle that can rotate relative to the frame.

Abstract: An exercise apparatus and method for working the hip muscles, in particular the glute muscle groups. Said exercise apparatus includes a low-profile chassis having a front portion and a rear portion, an elongated cross member having a pair of hip/lap cushions, a foot platform slidably mounted on the chassis, a shoulder/back support mounted on a support frame, a resistance member for loading the muscles of a user and a variable transmission adapted to act as a variable diameter pulley configured to reduce the input force required for a user to overcome the resistance member force.

Abstract: Apparatus for performing a pull down exercise comprising: a frame, a seat, an input arm assembly interconnected to a resistance mechanism and a manually graspable mechanism disposed vertically above the user's trunk in a start sitting exercise position, the input arm assembly being pivotably mounted on the frame for back and forth travel along a generally forward to rearward direction and along a generally side to side direction orthogonal to the forward to rearward direction, the input arm assembly being rotatably pivotable around a first linear axis and a second linear axis in the respective directions on exertion by the user of a rearwardly downwardly directed force on the manually graspable mechanism.

Abstract: A variable radius cam mechanism is configured for use in a weight lifting apparatus. The variable radius cam mechanism includes a disk configured to rotate about an axis. The cam mechanism includes a cable guide coupled to the disk and defining a path for a cable and a radial tangent distance between the cable and the axis. The cam mechanism further includes one or more actuators coupled to the disk and the cable guide and configured to move the cable guide relative to the disk to change the radial tangent distance during rotation about the axis. The cam mechanism includes a controller programmed to operate the one or more actuators to cause the one or more actuators to move the cable guide to change the radial tangent distance thereby changing a force transferred through the cam mechanism.

Abstract: A portable exercise ball-and-stick apparatus includes a base having an upper surface with a centrally-located concave spherical region located within the upper surface, a ball able to be located in the centrally-located concave spherical region of the base and a rod affixed to the ball for freely moving the ball within the centrally-located concave spherical region of the base. Preferably, the includes an additional concave spherical region having a spike centrally located in the additional concave spherical region with the spike extending vertically from a central region of the additional concave spherical region for receiving in a complementary slot situated longitudinally and on a side of the opposite from which the rod extends from said ball for when the exercise apparatus is not being used. Preferably, the rod includes a hand grip at the end of the rod distal to the ball with the hand grip being able to rotate or swivel relative to the rod.

Abstract: A lumbar decompression device may include one or more bases that support one or more uprights with a plurality of upper support members and a plurality of lower support members. The upper support members are configured to engage with a user's upper body and support a user's body weight. The one or more uprights are positioned laterally from the upper support members such that the user may perform a variety of movements of their lower body without contacting the one or more uprights.

Abstract: The present disclosure provides an exercise apparatus designed to allow a user to perform a gluteal bridge, typically with resistance, to improve the strength of the user's posterior hip and gluteal muscles. The exercise apparatus is configurable for use in different environments—in a gym, fitness center or training facility, a spa or studio, or a home gym. The exercise apparatus includes a frame assembly, a bench assembly, and a resistance assembly. The bench assembly is pivotally connected to the frame assembly to provide an elevated pivot point about which the bench assembly pivots when the user performs the gluteal bridge movement. The resistance assembly is operably connected to the bench assembly and provides a resistance force that the user overcomes in order to pivotally move the bench through the gluteal bridge movement. The resistance assembly can include a cable, pulley and weight stack, or an elastically deformable band.

Abstract: The present disclosure is directed to facilitating angled barbell exercises. An embodiment of the present disclosure includes an apparatus for facilitating angled barbell exercises which includes a receiving surface having a substantially concave front side including a central region and a back side; and a support frame coupled to the back side of the receiving surface, the support frame including a floor support having a planar surface and a wall support having a planar surface; wherein the planar surface of the floor support is horizontal and positioned to contact a floor; and wherein the planar surface of the wall support is vertical and positioned to contact a wall that is perpendicular to the floor.

Abstract: A weight plate for use in a weight stack of an exercise machine includes a locking member moveably attached to the weight plate between an interlocked position and an unlocked position. The weight plate further includes an interlocking magnet attached to the weight plate to retain the locking member in the interlocked position and an unlocking magnet attached to the weight plate to retain the locking member in the unlocked position.

Abstract: A multifunctional kinetic mechanism includes a base including a slant tube, a counterweight unit including a joint shaft rotatably connected to the slant tube of the base, a barbell shaft having a first end piece connected to the joint shaft and a second end piece opposite to the first end piece and a counterweight attached to the second end piece of the barbell shaft, and an operating unit including a main frame, a sleeve located at a front side of the main frame and sleeved onto the second end piece of the barbell shaft, two grips respectively pivotally mounted at an opposing rear side of the main frame and two shoulder cushion pads mounted at a bottom side of the main frame between the sleeve and the two grips. Thus, a user can operate the operating unit to move the barbell shaft to train different muscle groups.

Abstract: Multi-use exercise apparatus has a platform base with four spaced legs having non-skid lower surfaces. An elongated box member supports padded rollers mounted on an axle disposed laterally of box member and a releasable lock attaches the box member to a base. A base complemental socket fittingly releasably receives a box end. The lock has one biased lug engageable with a socket shoulder when box end is in socket, and a release lever to disengage the lug to permit removal thereof. Box member extends from socket at an acute angle to dispose the rollers above the base so that user's knee may engage a roller during some exercises. Other similar rollers are above the base such that user feet may engage same during other exercises. Differing thickness pads are releasably connected to form differing heights thereof for providing a user knee block limiting the squatting during some exercises.

Abstract: An exercise device including at least one attachment structure configured to be mounted to a support assembly. A first arm and a second arm pivotably connected to the at least one attachment structure. At least one bracket pivotably connecting an end of the first arm with an end of the second arm. At least one of catch member pivotably connected to at least one of the first arm, the second arm, and the at least one bracket. The at least one catch member is configured for accepting a weight bar.

Abstract: An exercising device includes a chair member having a seat element disposed on a base supporting member, two handles each include a lower portion rotatably attached to the base supporting member and each include a spring biasing member provided on the handle, a resistive device engaged with the handles for applying a spring biasing force to resist the rotational movement of the handles relative to the chair member, and two arm rests each include a bottom portion attached to the spring biasing member for supporting a forearm of a user and for allowing the arm rest to be pivoted laterally and upwardly and downwardly relative to the handle and the chair member with the spring biasing member.

Abstract: In one embodiment, an exercise apparatus for exercising an arm includes a lever adapted to attach to a wheel of a wheelchair, a forearm support pivotally mounted to the lever that is adapted to support a forearm of a wheelchair user during exercise, and a resilient member attached to the lever that is adapted to resist movement of the lever by the user.

Abstract: An apparatus for the development of upper body parts and muscles is disclosed. The apparatus includes a base on which is mounted a seat supported above the base and a forearm pad disposed forward of the seat and supported above the base. A pivoted lever is pivoted at a first end to a seat support, a second end of the lever extends past the forearm pad a distance and includes a weight supporting pin which extends vertically upward. A lifting device is selectively and pivotally attached to the pivoted lever forward of the forearm rest. A plurality of weights are selectively attached to the weight support pin to vary the amount of force required to use the lifting device and raise the weights. A variety of attachments are selectively affixed to the lifting device to exercise various body parts and muscles.

Abstract: An exercise apparatus is provided where a user selectively changes the amount of effort required to operate the machine on demand without interrupting the workout. A manual shifting process allows the user to selectively change the amount of resistance with the gravity included positioning of a resistance weight on a lever arm.

Abstract: Machines, apparatuses, systems and methods for providing adjustable tension to a cable system using a pivotally mounted leverage mechanism that employs an adjustably positionable weight. Embodiments are used in exercise and other muscle strengthening devices, and may include an electronic control system for monitoring, recording a user's progress, and for altering or releasing tension to the cable system based on feedback from the user. Embodiments include a user interface for inputting information for particular exercises or workouts, as well as outputting/downloading information following exercises or workouts.

Abstract: A dual-mode exercise apparatus may include an articulating arm assembly coupled through a joint to a support assembly. In an illustrative embodiment, the arm assembly may include a seat centrally mounted above a ball-and-socket joint and a stabilizer member for the hands and/or feet of the user. In a first mode of operation a user sits on the seat and uses his or her core muscles to articulate the seat on the ball-and-socket joint against the resistance provided by, for instance, weights mounted on distal portions of the arm assembly. In certain embodiments the apparatus may further provide a second mode of operation which simulates rowing a kayak. In a corresponding illustrative embodiment a user sits in a second seat positioned rearward of the arm assembly and the arm assembly includes handle members. In operation the user articulates the handles in a manner akin to rowing a kayak.

Abstract: An exercise arm apparatus and method of use. The exercise arm comprises at least one finger, a spindle attached to the finger, and weights sized to reside on the spindle. One end of the exercise arm is rotatably attached at a pivot point to a frame or to a vertical surface; a belt is attached to an opposite end of the exercise arm by means of a belt line. Where the exercise arm is rotatably attached to a frame, dip bars and chin bars are disclosed wherein an exerciser may perform dips and chins. Upward motion by an exerciser wearing the belt is impeded by spindle weights, a belt elastic attached at one end to the belt and at an opposite end to the exercise arm, and/or an elastic member attached at one end to the frame and at an opposite end to the exercise arm.

Abstract: A physical exercise apparatus is disclosed, and comprises a frame, a seat, an arm, and a pair of cycling hand pedals. The seat is supported by the frame and configured to support a user in an at least partially supine position. The arm is movably attached to a first portion of the frame and coupled with a linearly movable resistance load. The pair of cycling hand pedals is attached to a second portion of the frame and independently movable from the arm so that the user can cycle the pair of cycling hand pedals while separately moving the arm with a portion of his or her lower body.

Abstract: An exercise machine has a main frame and a user support movably mounted relative to the main frame for movement between a start position and an end position during an exercise. At least one user engagement device is movably mounted relative to the main frame for engagement and actuation by a user during an exercise, and a connecting linkage translates movement of the user engagement device to movement of the user support. A lifting arm is movably mounted relative to the main frame and associated with at least one of the user support, user engagement device, and connecting linkage so as to move during an exercise. A load associated with the lifting arm provides exercise resistance.

Abstract: A swiveling user support assembly has a user support or seat rotatably mounted on a user support mounting device or frame for rotation about a first pivot axis, while the mounting device or frame is pivotally or rigidly connected to a main frame of an exercise machine. The user support has a base, and a primary user support and stabilizing device mounted on the base. A pivot connection between the base and mounting device or frame allows the user support to swivel from side to side about the first pivot axis. A centering mechanism helps to orient the user support in a central position for user entry or exit.

Abstract: The exemplary embodiments herein provide an exercise device having a frame, comprising a first and a second arm, a first end of each arm meeting in fixed angular relationship at a vertex and a second end of each arm extending away from the vertex; a lever arm, having a first and a second end, the first end constrained to rotate about a pin located near the vertex; and a resistance arrangement, configured to convert rotation by a user of a first rotational assembly about an axis on the second end of the first arm into rotation of a second rotational assembly about an axis on the second end of the lever arm, which is converted into rotation of a third rotational assembly about an axis on the second end of the second arm, with the rotation of the third rotational assembly being resisted by a resistive element, the resistance arrangement providing a substantially constant resistance against the rotation of the first rotational assembly by the user over the entire range of the rotation.

Abstract: A floor of a gym's weight room is configured to encompass the installation of weight stations with weight towers controlled remotely from a control panel, with said weight station assembled atop a weight room floor. The floor of the gym, for each station-tower combination, includes two reinforced boxes embedded in the floor, each having an opening at floor level, wherein one box is located below the base of the weight station and one box is located in front of the respective weight tower, preferably positioned far from the station, the two boxes being connected by at least two parallel tubes located beneath the level of the gym's floor, and wherein the interior of each box is affixed with a cable pulley and bearing, each cable pulley being at a level so that the horizontal section of a steel cable runs toward a center of one of the tubes.

Abstract: An exercise arm apparatus and method of use. The exercise arm comprises at least one finger, a spindle attached to the finger, and weights sized to reside on the spindle. One end of the exercise arm is rotatably attached at a pivot point to a frame or to a vertical surface; a belt is attached to an opposite end of the exercise arm by means of a belt line. Where the exercise arm is rotatably attached to a frame, dip bars and chin bars are disclosed wherein an exerciser may perform dips and chins. Upward motion by an exerciser wearing the belt is impeded by spindle weights, a belt elastic attached at one end to the belt and at an opposite end to the exercise arm, and/or an elastic member attached at one end to the frame and at an opposite end to the exercise arm.

Abstract: An attachment for exercise equipment is disclosed. The attachment is a handle assembly with a compressible rotating grip mechanism. The grip mechanism includes a swivel grip rotatably attached to the handle, and a floating grip coupled to the swivel grip by one or more pins. The grip mechanism includes one or more springs between the swivel grip and the floating grip.

Abstract: A multi-use exercise device includes a shaft extending between ground-engaging support structures with a pair of arms rotatable around the shaft into a plurality of various angular positions relative to the ground providing a plurality of different exercises with a plurality of different levels of difficulty. The exercise device can be used as a support structure for pushup and planking exercises, as well as shoulder mounted weight support for squats and lunges.

Abstract: A weightlifting system according to an exemplary aspect of the present disclosure includes, among other things, a first frame member that extends along a longitudinal axis, at least one pair of openings disposed along the longitudinal axis. The at least one pair of openings are generally L-shaped and include a first opening and a second opening. A front face is mounted to the first frame member and extending along the longitudinal axis.

Abstract: A weight trainer with a load detection system includes a frame, a load detecting device, and a display device. The frame has a transmission device, a weight allocating device, and a stand. The transmission device is disposed on one side of the frame. The weight allocating device is connected to the transmission device and can undergo displacement in the vertical direction of the stand. The load detecting device is disposed beneath the weight allocating device. The load detecting device includes a sensor, a base, and a platform. The sensor is abuttingly disposed between the base and the platform. The display device is electrically connected to the load detecting device. Accordingly, the weight trainer with a load detection system is effective in detecting a weight change precisely, enabling a user taking fitness exercise to gain access to information thereof in real time, and quantifying the information.

Abstract: Disclosed is a weight control apparatus for a weight training machine. The weight control apparatus includes a plurality of stacks which are fitted to a pair of guides standing upright between supports on a base such that the stacks slidably move up and down, and which have rectangular locking holes; a body arranged on a front surface of the base, in which the body has a plurality of insertion holes corresponding to the locking holes of the stacks and is provided at an upper portion thereof with a holder; and a cover arranged on the front surface of the body and having a plurality of locking pin members inserted into the insertion holes.

Abstract: A machine for exercising at least a user's abdominal muscles, the machine having a base having front and back ends; an arm lever mounted to the base near the front end of the base; a user platform moved by a user and/or by the arm levers, the user platform slidably and pivotably mounted to the base; and a linkage mechanism operatively connecting the arm lever to the user platform so that when the arm lever is moved towards the user platform, the user platform is moved towards the arm lever and a front end of the user platform is moved upwards, pivoting the user platform into an angled configuration, and when the arm lever is moved away from the user platform, the user platform is moved away from the arm lever and the front end of the user platform is moved downwards, pivoting the user platform into a horizontal configuration.

Abstract: A weight training machine for allowing at least two of a user's muscle groups to push or pull simultaneously in a synchronized and unified fashion, having at least one common counter or weight resistance mechanism; a first actuating means operatively connected to the at least one common counter or weight resistance mechanism for allowing actuation of the at least one common counter or weight resistance mechanism by a first of the user's muscle groups, and a second actuating means operatively connected to the at least one common counter or weight resistance mechanism for allowing actuation of the at least one common counter or weight resistance mechanism by a second of the user's muscle groups, wherein actuation of both the first actuating means and the second actuation means simultaneously acts upon and or resists against the at least one common counter or weight resistance mechanism. One embodiment is an exercise machine and a drive or actuating mechanism with a lever and fulcrum configuration.

Abstract: A weight stack assembly for an exercise machine includes: a plurality of weights arranged in a vertical stack; a post extending through the weights, and a selector unit. Each of the weights includes an open-ended, forwardly facing slot, wherein the slots of each of a first set of the weights form a first column, and wherein the slots of each of a second set of the weights form a second column that is parallel to but non-coincident with the first column. The vertical stack is formed by alternating first and second weight. The post is configured to connect with a movement arm of an exercise machine and includes a first column of apertures that align with the slots of the first set of weights and a second column of apertures that align with the second set of weights. The selector unit is configured to be inserted into one of the slots and one of the apertures to select a portion of the weights to provide resistance for exercise.

Abstract: A weightlifting system according to an exemplary aspect of the present disclosure includes, among other things, a first frame member that extends along a longitudinal axis, at least one pair of openings disposed along the longitudinal axis. The at least one pair of openings are generally L-shaped and include a first opening and a second opening. A front face is mounted to the first frame member and extending along the longitudinal axis.

Abstract: A dual-mode exercise apparatus may include an articulating arm assembly coupled through a joint to a support assembly. In an illustrative embodiment, the arm assembly may include a seat centrally mounted above a ball-and-socket joint and a stabilizer member for the hands and/or feet of the user. In a first mode of operation a user sits on the seat and uses his or her core muscles to articulate the seat on the ball-and-socket joint against the resistance provided by, for instance, weights mounted on distal portions of the arm assembly. In certain embodiments the apparatus may further provide a second mode of operation which simulates rowing a kayak. In a corresponding illustrative embodiment a user sits in a second seat positioned rearward of the arm assembly and the arm assembly includes handle members. In operation the user articulates the handles in a manner akin to rowing a kayak.

Abstract: An exercise machine includes a frame, a body support assembly in pivotable engagement with the frame, and a counter balance assembly connected to the body support assembly, wherein, in operation, the body support assembly is pivotable from a downward position to a top position. The counter balance assembly partially balances a body weight of a user in a prone position against the body support assembly as the body support assembly is pivoted from the downward position to the top position. The counter balance assembly may include a reaction arm extending from a rear portion of the body support assembly and pivotable about the frame, and may include a weight bearing end opposite the body support assembly. A method of using an exercise machine includes positioning a user body prone against a body support assembly, wherein the body support assembly is pivotally engaged with an exercise machine frame and counterbalancing the user's bodyweight.

Abstract: A weightlifting system includes a weight bar frame rack having a first frame member that extends along a longitudinal axis. The first frame member includes a front face, a first side face, a second side face and a multiple of opposed pairs of openings disposed along the longitudinal axis. Each of the multiple of opposed pairs of openings are generally L-shaped and include a first opening and a second opening. A bracket assembly includes a mount having a first mount plate and a second mount plate spaced from the first mount plate. The first mount plate and the second mount plate are engageable relative to at least two opposed pairs of openings of the multiple of opposed pairs of openings.