Water supply backflow preventers

Swing check valve Swing check valve
Inline check valve Inline check valve
Dual check valve Dual check valve
Double check valve assembly (DCA)  DCVA
Double check valve with atmospheric port (DCAP) Dcap
Reduced pressure zone assembly (RPZ) RPZ
Anti-Siphon vacuum breaker Anti-Siphon Vacuum Breaker
Hose bib vacuum breaker Hose bib vacuum breaker

Thanks to Watts Canada for the use of the photographs.