CheckFlo Check Valves includes Single Door wafer pattern designs for small diameter and Nozzle Check Valves and Silent Check Valves for prevention of Surge and Waterhammer on pipelines. Valves, depending on design, are available in sizes DN50 to DN1200 and for pressure ratings of PN10, PN16, PN25 and PN40. Valves for higher pressures of PN64 and PN100 are available on request.