Pressure Switch Pressure Switch Application Air Compressor Manual Switch Action Auto/Off/Reset Pressure Switch Port Type (1) 3/8 in FNPT (3) 1/4 in FNPT (4) Port Pressure Switch Factory On/Off Setting 310/360 psi Pressure Switch Unloader 1/4 in Compression Pressure Switch Differential 40 to 105 psi Pressure Switch Range 40 to 360 psi Pressure Switch Electrical Contact Form 3PST Pressure Switch Action Standard Overload Protection 16 to 20A NEMA Rating 1 Series MDR3/OL