HDL Air Release Valves come in a variety of materials with flanged (DIN or ANSI) or threaded (BSP or NPT) connections, starting at 3/4" BSP or DN6 threaded up to 24" or DN600 flanged.

HDL Ball Check Valves come in a variety of materials with flanged (DIN or ANSI) or threaded (BSP or NPT) connections, starting at 1/4" BSP or DN6 threaded up to 24" or DN600 flanged.

Here you find special developments and parts, other than non return or air release valves.