Runleader RL-HM012C Inductive hour meter with tachometer for all Gasoline Engines and Diesel Engines ATV UTV dirtbike motobike motocycle outboards snowmobile pitbike PWC marine boat waterproof Digital tach hour meter tacometer for Gasoline Engines and Diesel Engines Accumulating total running hours TOTAL HOURS;Records and Displays to 9,9999 hours;Automatic Roll over.Resolution 0.1 hour. Measuring current engine RPM;Monitors RPM and Hours on any rotating shaft, pulley, or rotating object No Battery Required.When engine is working, it displays RPM; when engine is stopped, it displays total running hours Waterproof IP68 ,100% epoxy encapsulated casing resists water.