Milton Industries is proud to be the creator and leader of the pneumatic industry standard M-Style coupler. This 1/4 inch FNPT M style brass coupler has a 1/4 inch basic flow size, offering a maximum of 300 PSI. Comes with Buna-N seal and air flow of 40 SCFM. Milton M-Style Kwik Change couplers are made of brass, while M-Style Kwik Change plugs are made of case-hardened steel and are plated to resist rust.