Kronos 2" Water Pressure Gauge Kit - 30 PSIPolished Stainless Steel bezel, flat glass lens, perimeter lighted spun aluminum dial with Gold and Black graphics. Gold increments and Logo on dial are Embossed. All instruments include two piece Newport pointer with White hub. A pressure gauge operates by sending a low amperage current through the gauge&';s meter to ground via a sending unit with variable resistance. The resistance of the sending units increase or decrease with the changes in pressure, temperature, etc...As the sender&';s resistance varies, the amount of current allowed to flow through it to ground changes and the meter deflects, showing the change in pressure.2" - Hole size: 2.0625" (53mm)Specifications: Flat Scratch Resistant Lens Polished Stainless Steel bezel LED Illuminating around the Perimeter of the Dial Newport style White Pointer Dual Scale - Imperial and Metric In the Box: 2" 30 PSI Kronos SS Water Pressure gauge 1/8" NPT Adapter w/locktite VS 516 Mounting hardware 15&'; Tubing Factory P/N OP1171*Sold as an Individual**Gauge Cover not IncludedThis product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns. Specifications: Gauge Type: Water Pressure Series: Kronos Voltage - Input Range (Volts): 12/24 V Gauge Size: 2" Box Set: No Box Dimensions: 5"H x 6"W x 6"L WT: 0.7 lbs UPC: 759266190078 Quick Guide (pdf)