Spring-actuated valves open and close by liquid flow. Bronze body with type 304 stainless steel spring. Can be mounted vertically (flow up only) or horizontally. Material meets ANSI B2.1, ISO 9002, MSS SP80, and ASTM B584, C89844 standards. Threaded ends meet ANSI B2.11 standards. Sweat ends meet ANSI B16.18 standards. Note: Not for use as a foot valve or reciprocating air compressor service.