Square D brand Pumptrol air compressor pressure switch model 9013FHG12J52M1X 95-125 PSI with unloader control valve and On / Off switch. This pressure switch is designed for a single stage air compressor pumping up to 125 PSI but can be adjusted anywhere from 70-150 PSI. This switch features a built in On / Off metal lever and also a unloader located on the bottom of the switch. The unloader is used to unload head pressure off the compressor pump for a load free start up.
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