Hitachi Power Tools 191021 1/4" Pneumatic Male Coupler Fitting: * Male coupler fitting * Couplers have hardened steel balls to ensure connection holds tight under the most rugged applications * Standard couplers have a built in sleeve guard to prevent accidental disconnect and stainless steel springs * Industrial Milton style * Plated steel * 1/4" fitting * 3/8" Male NPT * Carded