The Watts 3/4-in FNPT Iron Pressure relief valve Model #3/4 374A 030 is a high-quality HVAC and refrigeration part designed for use in systems requiring a 3/4-inch diameter connection. Made of durable iron material, this pressure relief valve has a length of 34 inches and features a dependable Watts brand name. It is a crucial component for regulating pressure in HVAC and refrigeration systems, ensuring optimal performance and safety. these pressure valves come new without box.