3/4", ASME 30 LB Pressure Relief Valve, For Hot Water Heating & Supply Boilers, Pressure Protection Only, Standard Pressure Setting Is 30 PSI, Maximum BTU Input At 30 PSI Is 650,000 BTU, Bronze Body Construction, 3/4" Female Iron Pipe x 3/4" Female Iron Pipe Connections, HV, NB & ASME Listed.