The Square D 9013FHG42J59M1X is a single-port Pumptrol pressure switch that automatically controls air compressors and other pumps by cycling the circuit as pressure reaches the setpoints. It has a 1/4" FNPS thread and a 135–175 psi switching range with a fixed 40 psi differential (on at 135 psi, off at 175 psi), commonly used on two-stage compressor units. The unit includes an unloader valve and an On/Off switch, aligning with the Square D 9013FH family for reliable control of pressurized systems.
