Features Main Function: Used to regulate the pressure, when the system pressure is sufficient, close the air inlet to make the machine idle. Working Principle: High pressure medium is filled into a relatively large cavity through a small hole to achieve pressure reduction. Easy Adjustment: With compressed air as the power source, cylinder as the actuator, the valve is driven to realize on off or proportional adjustment. Standard Inlet: The air compressor pressure control switch has NPT 1/2in 4 port inlet to ensure stable connection and no air leakage. Durable Material: The pressure switch shell is made of polyurethane, which is wear and corrosion resistant, and has a long service life. Specification: Item Type: Pressure Switch Product Material: Polyurethane Inlet: NPT 1/2in 4 Port Pre Calibration: 90-120PSI Package List: 1 x Pressure Switch Package List 1 x Pressure Switch