BLH8S by ZSi-Foster | Quick Disconnect | FHK Series | 1" Two Way Shut Off | 1" Socket | Ball Lock | SteelInterchange: Compatible with ISO 7241 1, Series B. Applications: FHK Series sockets incorporate valves in both socket and plug halves to prevent fluid loss when the socket is disconnected. These sockets are normally referred to as "hydraulic couplings", but they are used extensively with other media where objectionable. The FHK Series sockets are available in ROHS compliant steel and brass. Features: Type: FHK, Two Way Shutoff , Both socket and plug