Watts Series SS07F Stainless Steel, Single-Detector Check Valves for Fire Sprinkler Systems are used in fire protection applications to detect leakage or unauthorized use of water in fire sprinkler systems. It consists of a stainless steel body construction with flanged connections, and stainless steel linkage parts. Series SS07F is lightweight, non-corrosive, and can be installed in horizontal or vertical positions. A meter bypass assembly and bypass tapings are optional.