This tachometer is a high quality instrument for measuring revolutions per minute (RPM) with a wide measuring range and highresolution.It is featured with high precision measurement, fast measuring time and long detection distance up to 500mm (20inch) with laser.This tachometer is very easy to use by applying a reflective strip (included in the package) on the target object, then aim at the mark by a laser beam.This tachometer has a wide range of applications, such as measuring rotating speed of machine, motors, wheels, lathe for metal or wood cutting work, etc. Features: Non-Contact handheld digital tachometer with stable performance. Automatic and manual measurement mode for selection. Wide measuring range (2.5 to 99,999 RPM) and high resolution. MAX./MIN./AVG.values recording function. data hold, data hold and recall (60 readings). LCD display with white backlight, easy to read. Capable of measuring at a distance of 2-20in (50-500mm). Auto and manual power off. Low battery indication. Features: Color: Blue/Red (Optional) Material: ABS PLASTIC Measuring range: RPM 2.5 to 99999 Resolution: 0.1RPM to 2.5~999.9RPM;1RPM to 1000 ~ 99,999RPM Accuracy: 0.02% + 1 digits Measuring distance: 50 ~ 500 mm / 2 ~ 20 inches Sampling time: 0.5s (above 120RPM) Data storage capacity: 60 readings Auto Power Off: After 20 years Operating temperature: 0 to 50 (32 to 122) Operating humidity: 10 to 90% relative humidity Storage temperature: -10 to 60 (14-140) Storage humidity: 10 to 75% relative humidity Power supply: 1*9V 6F22 battery (not included) Product size: 145 * 90 * 35mm / 5.7 * 3.54 * 1.4in Product weight: 79g / 2.81oz Package size: 20*14*4cm/7.87*5.5*1.57in Package Weight: 134g / 4.73oz Note: 1. You need to stick the reflective strip on the target object before measuring. 2. Do not direct the laser beam at eyes directly;Safety glasses is recommended. 3. Do not use near explosive gases or in other potentially explosive areas. Package list: 1 * digital tachometer 1 * Reflective Tape 1 * User Manual (English)