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 215/250 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 4 to 6.3A NEMA Rating 1 Series MDR3/OL