Feature: Applying the MCU and electrooptical technology, can perform contact measurement of rotating & linear rolling speed efficiently. 0.5-19999RPM, wide measuring range and high resolution. Large LCD display with clear reading. Automatically store for the MAX, Min and LAST value. Accessories convertible for different measurement. Equipped with convex channel lineal rate sensor, it is convenient for measuring the lineal rate of the wire, cable. ropes etc. Low battery indication so you can know when need to replace the battery. Solid structure built with durable electronic elements and light ABS plastic house Specification: Brand SMART SENSOR Model AR925 Measure range 0.5-19999RPM 0.05~19999.9m/min 0.2~6560Ft/min Resolution ratio 0.1RPM, 1RPM 0.01m/min, 0.lm/min 1Ft/min Measure error ±(0.05%+1 digit） Sampling frequency 0.8Sec Max/Min Yes Equipped with multi sensor Yes Low power notice Yes Measure method Contact Data lock Yes LCD backlight Yes Working temperature 0~50o℃ Storage temperature -20~70℃ Power 3*1.5V AAA battery (Not include) Weight 132g Product size 190*55*35mm Package list: 1 * Digital Tachometer(without battery) 1 * User manual 1 * Accessory(Bag) Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product. .