Tracks service time and rpm of your machine; perfect for timely oil changes, valve adjustments, spark plug replacements, etc. Resettable maximum rpm Usable with any gasoline engine Adjustable input for dual or single spark ignition systems Includes log book for writing down oil changes, valve service, and more Real time reading of tach up to 20k rpm Record total hours accumulated up to 9,999.99 hours; not resettable/erasable Peel and stick or attach with enclosed hardware Connects to spark plug wire; no batteries are required Safely and completely encased in 100% epoxy. METER HOUR/TACH