Quick-action couplings, also known as quick-connect or quick-release couplings, are devices designed to connect and disconnect fluid lines rapidly and efficiently without the need for tools. They are commonly used in hydraulic, pneumatic, and other fluid transfer systems to facilitate the swift connection and disconnection of hoses, pipes, or tubes.

A poppet valve is a type of valve used in quick couplings to control fluid flow. It consists of a movable element (the poppet) that seals against a seat, blocking or allowing fluid passage. In quick couplings, poppet valves ensure a tight seal when the coupling is disconnected and enable smooth, leak-free fluid flow when connected.