Pressure Switch Air Compressor Manual Switch Action None (1) 3/8 in FNPT (3) 1/4 in FNPT (4) Port Pressure Switch Factory On/Off Setting 310/360 psi No Pressure Switch Unloader Pressure Switch Differential 40 to 105 psi Pressure Switch Range 40 to 360 psi Pressure Switch Electrical Contact Form 3PST Pressure Switch Action Standard NEMA Rating 1 Series MDR3 HP @ 1 Phase - 120V 2 hp HP @ 1 Phase - 240V 5 hp HP @ 3 Phase - 240V 7 1/2 hp HP @ 3 Phase - 480V 15 hp