A closure, buckle, or clasp for connecting two free ends of a strap, a belt, a necklace, or a harness is disclosed that relies upon a mechanical keeper to at least aid in keeping the closure in an engaged condition, wherein the mechanical keeper is of magnetic material and is biased in a locked position by means of the force field of a magnet, thereby eliminating all springs or snug-fitting elements that could wear or lose their effectiveness over time. The magnetic keeper and the magnet may be parts of the same clasp element or they may be parts in separate clasp elements that are joined to effect closure of the clasp.

A magnetic closure for bags, rucksacks and items of clothing, comprising a first element and a second element that are suitable to couple to each other, each one of the first and second elements accommodating internally at least one permanent magnet; each one of the first and second elements comprises a base provided with male engagement elements and female engagement elements, the male and female engagement elements of the first element being able to mutually couple respectively to the female and male engagement elements of the second element.

A magnetic buckle. The magnetic buckle includes a male buckle having a magnetic element, and a female buckle having a magnetic element. The magnetic elements of the male and female buckles facilitate the alignment of the male buckle with the female buckle when they are positioned horizontally opposite to each other, as well as the steady insertion of the male buckle into the fit-in groove of the female buckle under the influence of the magnetic attraction. The male buckle can be prevented from slipping off vertically from the female buckle even under an external force, and this arrangement further provides a stronger resistance to the buckled state against any horizontal pulling force.

A pyrotechnic release mechanism is actuated by an electrical signal from a remote telemetry actuator such as a radio transmitter to cause two normally connected parts to separate. When used as shown with an animal collar mounted data acquisition system, the two parts can be separated to release the collar. If desired, a separate data storage device can be released to permit stored data to be recovered. The device comprises two parts with interfitting members normally held in position with a coupling pin. A pyrotechnic device is positioned behind the pin, and upon firing, the pin is moved sufficiently to clear one of the members at least, so that the two members will then separate. The device can be used to permit remotely controlled recovery of a part that is normally mounted together and which are to be separated. The movement of the separating pin after actuation can also be used for energizing a transmitter or signaling circuit that will send out a locator signal to simplify retrieval of the parts to be recovered. The linear actuation of the separating pin ensures simplicity of operation and reliability.

Slip prohibiting engaging portions provided in a female member and a male member elastically fit with each other in the crossing direction relative to a sliding and fitting direction when the female member and the male member are slid and fitted with each other to give a predetermined resistance when the female member and male member are pulled out.