Motorcycle tachometer timer

Features:1. Works on all spark ignition engines by selecting engine type using S1 and S2 buttons.2. One is to be wrapped around a for spark plug wire and the other is a ground wire.3. Wide operating temperature range.   Purpose: to measure speed Voltage: 3 (V) Power: 0.002-0.03 (W) Size: about 52*46.8 (mm) Colour: Black Applicable models: Motorcycle lawn mower Display screen: LCD screen display Battery life: 2-3 years   Power supply: Inductive design, only need to tie the connection cable to the spark plug to work