Sempell AG manufactures isolation valves including stop check valves for a variety of applications. Models include the HP series stop check valve and specialty isolation valve with pressure ratings of PN 500 class 2680. Sempell's stop check valves com in sizes ranging from 1/25" to 3".

The W.T.A Valve company manufactures spring loaded non-return-valve in straight type, y-type or corner-type; with flanges or buttweld ends; can be supplied in carbon steel 1.0619 (WCB), stainless steel 1.4408 (CF8M) and special materials.