Marketing InformationFull port, positive shut-off ball-type design permits trouble-free servicing operations and water heater performance. dual O-ring stem seals are maintenance-free and designed to seal under pressure and temperature fluctuations. Captured union nut and adapter tank connections permit unlimited valve positioning and ease of installation onto all tankless water heater-types. Integral drain valves feature 1/4-turn lever handle operation and tethered caps, allowing heater air purging and flow rate testing as well as de-scaling and other maintenance operations. 150 psi pressure relief valve included in some kits. Available in 3/4 or 1 in FNPT union tank, by 3/4 or 1 in FNPT, sweat, copper press, PEX (F1807) or cold-expansion PEX (F1960) system connections.