... USA Industrial Type Air Couplers(Air Coupler, Air Tool Coupler, Quick Fitting), Milton type; Body size: ... Industrial Type Air Couplers, Milton type(Air Coupler, Air Tool Coupler, Quick Fitting); Body size: 1/4", 3 ... 1 / 4", 3 / 8", 1 / 2"; Coupler type: Milton type, Industrial type; Surface treatment: Zinc plated ... sockets and plugs will be strictly tested for its working pressure, air leakage, surface ...