This non-contact tachometer is a professional and practical motor speed meter to measure the revolutions per (RPM) with wide measuring range and high resolution. It's featured with high accuracy measurement, quick measuring time and long detecting distance up to 500mm(20 inch). This tachometer is easy to use by applying a reflective tape(included 3 in package) on object, then aim at the by beam. This tachometer has wide range of applications, such as measuring rotating speed of machine, motors, wheels, lathe for metal or wood cutting work, electrical fan, paper making, plastic industry, fiber, washing machines, car making etc. No-Contact handheld digital photo tachometer with stable performance. Automatically record the MAX. value, Min. value and Last value with low battery indication. Capable of measuring at a distance from 2-20in(50-500mm) with LCD display. 0.8 Second sampling time and 5-digit 18mm 0.7 inch LCD display with non-contact RPM measurement. Measuring Range: 2.5RPM - 99,999RPM Resolution: 0.1RPM at 2.5-999.9RPM, 1RPM at 1000-99,999RPM Accuracy: (0.05%+1 digit) Time Base: 6MHz Crystal Oscillator Test Range Select: Automatic Switching Function: Display Last Value, MAX. Value, Min. Value Power Supply: 1 x 9V 6F22 Battery(NOT Included) Power Consumption: . 30mA Working Temperature: 0-50(32-122) Material:plastic colour:Black Package Contents: 1 x Digital Tachometer 3 x Adhesive tape 1 x Carrying Bag Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.