Open a 3-3/8 inch diameter and 2-7/8 inch depth hole, insert the gauge, and secure it in place. Connect the three wires: power, ground, and lighting. This is a complete unit that works directly with the sensor—no additional sensor cables required. Mount the sensor in any position, on or under the dashboard. Initial signal acquisition takes approximately 30 seconds, with subsequent startups under 3 seconds. Performance improves with a clear view of the sky. If signal is lost, check all wiring connections and restart the device. Displays current speed and odometer (non-resettable); does not include a trip meter. Features low power consumption, long service life, high precision, fast satellite signal acquisition, and quick startup. Speedometer range: 220 km/h Voltage: 12V/24V Application: Universal fit Color: As shown in images Material: ABS + metal Dimensions: 75mm x 90mm x 85mm Package includes: 1 x 220 km/h Speedometer 1 x User manual (English and Chinese) 1 x Multi-plug socket Note: Lighting conditions and screen settings may cause slight color variations between the product image and the actual item. Measurement tolerance is +/- 1-3 cm.