Euro Black 2" Cylinder Head Temperature Gauge (60 to 220Adeg F) with SenderPerimeter-lighted Black dial with bold White graphics, Black aluminum bezel, contoured White pointer, and flat glass lens.A temperature gauge operates by sending a low amperage current through the gauge&';s meter to the ground via a sending unit with variable resistance. The resistance of the sending units increases or decreases with the changes in pressure, temperature, etc. 2" - Hole Size: 2.0625" (53mm)Specifications: Anti-scratch glass lens 12 VDC negative ground Perimeter-lighted Black dial Can be adapted for 24 VDC systems Factory P/N GP9438*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: Cylinder Head Temperature Gauge Size: 2" Series: Euro Black Box Set: No Voltage - Input Range (Volts): 12/24 V Box Dimensions: 2"H x 3"W x 3"L WT: 0.5 lbs UPC: 759266128194