The V-53 are in-line, quarter-turn, ball-type shutoff valves. Gas may flow in either direction. All are designed for pipeline service with any common, non-corrosive, non-toxic industrial gas. The V-53 is available in shutoff/check valve combinations for use at station outlets. The check valves are also available separately as adaptors for coupling a station regulator or outlet hose to any shutoff valve. All check valves have a neoprene ball seat which prevents gas backflow into the piping system as required by NFPA Standard 51.