Install Operation: Wrap the end of the induction wire around the spark plug tube 5 times, then fix it with a cable tie, then insert one end of the induction wire into the groove on the back, find a suitable position, and fix the watch with screws. Inductive Digital Hour Meter Waterproof LCD Display for Motorcycle ATV Snowmobile Marine Boat Ski Gas Engine, not tachometer model Features: Brand new and high-quality Track the service life of vehicle oil changes, valves, adjustments, spark plugs, etc. Easy to install Peel and stick No battery needed - connect to for spark plug wire Works on Any Gas Engine Record and display to 9,999.9 hours Hourglass symbol appears and flashes on/off to indicate counting time Automatic rollover Resolution: 0.1 hour epoxy encapsulated casing resists water, shock, stand fire of 85°C Specification: Item size: 54*36.5*14.5mm Packing content: 1 x Hour meter 1 x Wire 2 x Screw Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.