Specification: Item Type: Tachometer Color: Silver + Blue Housing Material: Aluminum Measurement Range: 0-16000rpm/min Voltage: DC 12V Outer Diameter: 65mm/2.6inch Inner Diameter: 58mm/2.3inch Package Weight: 245g Fitment: Universal Package List: 1 * Tachometer Note: 1. Please allow slight error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. How to Use: Two long lines L: red to positive pole: black to negative pole; three short lines: black to positive pole, green to negative pole, black/yellow to the engine speed signal line (the speed signal line of most is connected to the igniter output to the high voltage positive line, it can also be wired due to the trigger line.