Characteristics: It is used to measure the rotation of a car engine. The measuring range is 0 8000 RPM. /min. High accuracy and easy operation. Works on 1 2 3 4 5 6 7 8 cylinder gasoline vehicles or 1 - 2 cylinder new motorcycles. Adjustable gear shift light on the face. Note: 1. It is normal that the indicator is not zero in the absence of installation. After switching on, the product will check and adjust the indicator by itself. 2. If the product indicator is still not zero after power on, it can start normally when the indicator is above zero, it can be restarted to adjust the indicator after power off. Technical data: Black color Material: ABS Background light: blue light Input voltage: 12V Package size: 14 * 14 * 14cm / 5.5 * 5.5 * 5.5in Weight: 367.5 g / 13 oz Package List: 1 * 3.75 "Tachometer Gauge 1 * Installation Guide! 1 * Matching Package Note: NOT suitable for diesel vehicles, only for 12V gasoline vehicles