100-130 psi, 4 Port with bleeder, Powermate pressure switch is durable and long lasting. New Powermate pressure switch allows air compressor to run at its most efficient capacity, turning on and off the motor at the correct PSI. The Powermate pressure switch is part of the large line of Powermate genuine replacement parts. A pressure switch regulates air pressure in the compressor. Replace a pressure switch with a new Powermate pressure switch if the compressor motor is cutting out or not turning on at the proper psi.