HBP/CBP - High/Commercial Back Pressure APPLICATION, R134a Refrigerant, 115V 1 Phase 60Hz, 1/3 HP, High Start Torque (HST) 4528 BTU Capacity, 0.3125" Sweat (5/16" ODF) SUCTION LINE SIZE, 0.250" DISCHARGE LINE SIZE, Induction Run (RSIR/CSIR), Standard Efficiency Reciprocating Compressor (Model:AE4440Y-AA1A)