A pressure relief valve (PRV) is recommended in all installations and is mandatory in any installation in which the water flow can be restricted between the heater outlet and the pool/spa. 

Features:

• Pressure relief valve 3/4 in. 
• Brass nipple 3/8 in.
• Reducer brushing 3/8 in. M to 3/4 in. F NPT
• Elbow 90 degrees 3/4 in. NPT brass
• PTFE (Teflon) Tape