Abstract: A bistable member including a bistable, invertable dish- or dome-shaped base portion and an engaging projection extending therefrom. A male member is engaged with the bistable member by pressing the male member against a central apex of the bistable member that is surrounded by the engaging projection, thereby inverting the bistable member from a first stable form to a second stable form. In the second stable form, the engaging protrusion and a portion of the bistable member wrap around a knob of the male member, thereby securing the male member to the bistable member. A subsequently applied triggering energy re-inverts the bistable member, thereby releasing the male member. This assembly is usable as a snap fastener by setting an equilibrium point of the bistable member such that a relatively large triggering energy is required to re-invert the bistable member.

Abstract: A one-piece elastic fastener includes a pair of spaced elastic, generally dish-shaped head members adapted to fit on opposite sides of pieces of material to be joined. The head members each have a rim and are disposed concavely inwardly with their rims facing each other. An elastic shank member joins the head members and is adapted to pass through an opening in the pieces of material. In one embodiment an elongated loop member is centrally attached to one of the head members and is adapted to pull it through an opening in the pieces of material to be joined. In another embodiment a boss is positioned on one of the head members and a hook is used to pull it through the opening.

Abstract: A one-piece elastic fastener includes a pair of spaced elastic, generally dish-shaped head members adapted to fit on opposite sides of pieces of material to be joined. The head members each have a rim and are disposed concavely inwardly with their rims facing each other. An elastic shank member joins the head members and is adapted to pass through an opening in the pieces of material. An elongated loop member is centrally attached to one of the head members and is adapted to pull it through an opening in the pieces of material when the head member is folded back to divide it into two generally flattened halves extended outwardly of the fastener. The fastener is made of elastomeric material having a durometer of between about 65 and 75.