RPM Handheld Laser Infrared Motor Tachometer 1. Measurement range: 2.5 - 99999 rpm 2. Resolution: 0.1 rpm for 2.5 - 999.9 rpm; 1 rpm for 1000 - 99999 rpm 3. Measurement distance: 50 - 500 mm 4. Time base: 6MHz quartz crystal oscillator 5. Data storage: 20 sets 6. Range selection: automatic switching 7. Power supply: single 6F22 9V battery (not included), rechargeable batteries not supported 8. Power consumption: Approximately 35mA 9. Test value: value after 4 consecutive tests after power-on 10. A tachometer is a commonly used instrument in the machinery industry, used to measure the rotational speed and linear velocity of motors. It can precisely measure the rotational speed of impellers, rollers, and shafts, and is widely used in industries such as motors, fans, washing machines, textiles, automobiles, airplanes, and ships. 11. It adopts non-contact measurement, allowing measurement without contact with rotating parts. 12. A high-definition large-screen backlight ensures accurate readings regardless of environmental changes, whether day or night.