Pressure Switch for Air Compressor Regulator Mounting Accessories Reducer Description: [Material of part of this air compressor] Made of metal pressure gauge. This is a canonical element. To install the product on the board, use glue [Maximum current] 16-20A. Pressure range: 90-120 psi. Male thread diameter: approx. 21mm (1/2"NPT). Valves external thread diameter: 13 mm (1/4" NPT). Indicators diameter 1-1/2 ": 0-180 PSI. [With 2 connectors] Black on/off button. Automatic control, automatic loading/unloading. Connection of air tank pipes 1/2 with a diameter of 21 mm requires its own installation. [Note] If the pressure is lower than 90 psi, turn on the compressor. If the pressure is higher than 120 psi, turn off the compressor. Compressor switch control can automatically control the air compressor pressure. [Energy Saving] Standard air compressor pressure switch control valves designed to save air compressor electricity. Size Chart: 13.5 cm / 5.31 inch The package includes: 1 Pressure valve switch assembly