Stainless Steel Quick Connect Couplers SH,SM,SF,PH,PM,PF serieris of 20,30,40,400,600,800. Stainless Steel Quick Connect Couplers SH,SM,SF,PH,PM,PF serieris of 20,30,40,400,600,800. One-way automatic shut-off valve in the socket. Fulfils the requirements for compact, easy, rapid connection and disconnection ofmachinery.Suitable for use in hydraulic, pneumatic, fluid transfer, and vacuum systems.