Dwyer MP-001 Mini-Photohelic® Differential Pressure Switch/Gauge is a versatile device suitable for air and non-combustible gases. With an accuracy of ±5% FS at 70°F, it operates with a power requirement of 24 VDC / 24 VAC. The gauge face, mounted in a vertical position, features push-button set point adjustment and includes (2) SPDT relays. Its compact design, measuring 4-1/8" depth x 3-1/16" diameter, makes installation easy. Compatible with 3/16" ID tubing, it comes with standard accessories including mounting screws and a .050" hex allen wrench.