Features 1. This product can be used for all gasoline engines with spark plugs. This tachometer is easy to use and is suitable for two-stroke single cylinder, four stroke dual cylinder, and gasoline engines that ignite once per revolution; More suitable for gasoline engine testing of chainsaws and lawn mowers, with a measured RPM range of 100RPM to 30000RPM. 2. Due to the inductive design, the speed can be measured by simply placing it close to the engine spark plug cable. 3. Multiple measurement methods: Hold the instrument between 3-5CM of the spark plug cable and conduct the test; After installing one end of the electronic wire on the hole of the electronic watch housing, use a metal clip to clamp it on the spark plug cable sheath for inductive measurement. 4. The chainsaw tachometer timer has an LED LCD display, low voltage design, built-in power supply, and is safe and reliable. System data recovery function. Specification Material: ABS Color: Black Size: 10 x 10 x 7 cm Weight: 70 g Package Include: 1x Chainsaw tachometer timer