Dwyer Instruments - 1213 Gas Pressure Manometer. Designed for use with natural gas, the manometer can also be used to monitor any compatible gases up to 15 inches of water column. Tap water is used as the sensing media and a magnetic clip provides temporary or permanent mounting. Economically priced and made of durable plastic for years of trouble-free service. Includes three feet of vinyl tubing and 1/8" nylon male NPT to barb fitting. SPECIFICATIONS Temperature Limit: 140°F (60°C) maximum. Pressure Limits: 15" in. w.c. (381 mm). Piping Connections: 1/8" male NPT connector provided. Wetted Materials: Vinyl, PVC and Nylon. Weight: 5 oz (142 g).