Open a 3-3/8 inch diameter and 2-3/4 inch depth hole, insert gauge and secure in place. Features a stepper motor-driven pointer for accurate engine speed display, along with an LCD screen that clearly shows mileage. Initial signal acquisition may take a moment, but subsequent startups are fast, typically under 3 seconds. Performance improves with clear signal reception. If signal is lost, disconnect and reconnect all wires, then restart the device. Tachometer compatible with car, truck, boat, diesel generator engine, and gasoline engine applications. Speedometer range: 120 km/h. Operates on 12V or 24V. Low power consumption, long service life, high precision, quick signal acquisition, and short startup time. Color: black. Material: stainless steel. Size: 85mm. Package includes: 1 x 120 km/h speedometer, 1 x user manual (English), 1 x multi-plug socket. Additional items not included. Note: Lighting and display differences may cause slight variations in color between image and actual product. Measurement tolerance: +/- 1-3 cm.