Air-line fitting

Also known as pneumatic couplings, quick disconnects, air couplers, quick connect couplers, and quick couplers, hand-operable air-line fittings allow manual disconnection of gas supply lines, including compressed air and breathable air (a subset of breathing gases).

A coupled pair consists of a male nipple or plug and a female coupler or socket.

Fitting profiles have identifiable geometry on the male end, but care must be taken to use a compatible coupler.

Couplers use springs and balls to lock mating nipples into place.

A seal is effected using O-rings along the shaft of the nipple or by compression by the tip.