This Milton M-style 3 in 1 Manifold Kit includes (1) #685-4 Manifold, (3) #716 Couplers, and (1) #727 Plug, all at 1/4" basic flow size. Milton's M-Style KWIK-CHANGE couplers are made of brass, while the M-Style KWIK-CHANGE plugs are made of case-hardened steel and are plated to resist rust. This collection of couplers and plugs will interchange with all manufacturers who comply with the dimensional requirements of military specification MIL-C-4109. Please see below for more features and specifications.