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 a few seconds, less than 3 seconds in subsequent starts. Performance improves with a clear view of the sky. If signal is lost, check all wire connections and restart the device. Displays current speed and odometer (non-resettable); no trip meter included. Features low power consumption, long service life, high precision, fast location confirmation, and short startup time. Speedometer range: 220 km/h Voltage: 12V/24V Application: Universal fit Color: As shown 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 and display differences may cause slight color variations between the image and the actual item. Measurement tolerance: +/- 1-3 cm.