WW0888907, Watts, 6-8 Backflow Preventer First Check Rubber Parts Replacement Kit, 775 And 775Dcda

This 6-8 IN first check rubber parts replacement kit for series 775 and 775DCDA prevents the backflow of fire protection system substances from being pumped or siphoned into the potable water supply. It consists of a first check assembly O-ring and check disc. It is designed for installation on applications identified by local authorities as non-health hazard, such as on fire protection systems.