Schrader quick-connect air coupling plugs prevent accidental disconnection during use. The twist-lock design pushes to connect and lock in place, but requires a slight twist on sleeve to uncouple. Also known as Schrader twist-lock interchange plugs, these plugs are the male end of coupling sets. Also called nipples, they're inserted into the coupling bodies (female ends) and are compatible with Schrader sockets of the same size. Tubular air flow valve minimizes pressure drop and air or fluid loss. These multipurpose couplings connect air tools and hoses to compressed air supplies for drop-down air lines, air compressors, and pneumatic tools.