RACETECH Electronic Hourmeter - Wireless/Erasable HOURMT002NRWireless, vibration activated, no battery or wire connection problems, works on trailers, motors, machinery, equipment Two different sensitivity levels, resolution 0. 1 Hours Maintenance services: clean air filter flashes every 5 hours, change oil alert every 10 hours, valve service every 20 hours Partial counter reset, total hours can not be reset 100% Waterproof ip68, service life 5 years Suitable for 2 and 4 stroke engines, one, two or four