This Watts 1/2" No. 53L Water Heater Pressure Relief Valve is brand new and comes in an open box. The valve is suitable for use with water and has a body made of bronze. It has an inlet diameter of 1/2" and an outlet diameter of 1/2". The valve is manually operated and has a capacity of 15,000 BTU/Hr. It has a 1/2" NPT connection and is ideal for use with water heaters.