Features: 12 IN 1 CONTACT AND PHOTOELECTRIC TACHOMETER: The digital tachometer integrates 2 measurement methods, contact and photoelectric non contact. The tachometer can be used for photoelectric speed measurement, light source scintillation frequency measurement, contact speed measurement and contact linear speed measurement 2ACCURATE AND UNIVERSAL: can be widely used in motor, fan, paper, plastic, chemical fiber, washing machine, automobile, aircraft, ships and other manufacturing industries, especially with different rubber contact wheels can meet the user in any occasion to accurately measure the contact speed 34 CONTACT PROBE OPTIONS: The tachometer is equipped with 4 different contact probes, which can be selected according to different scenes to achieve close contact with the object being measured. RPM tachometer is suitable for measuring the speed of conveyor belts, levels, pulleys, etc. 4CLEAR LCD: The digital tachometer is equipped with a large LCD display for clear reading, very convenient 5DATA RETENTION: The digital tachometer features a high definition backlit display that can be read clearly even in dark conditions and automatically saves the maximum, minimum and holds the last value, so you don't need to worry about shutting down due to low power consumption or unexpected power outages Item Type: Battery: 4 x 1.5V AA battery(not included) Features: Photoelectric contact tachometer or line tachometer 5 bit large screen LCD display, word height 18mm Wide measuring range and high accuracy 10 new surface speed sensors with groove type slots for easy measurement of wire, cable and rope speed and length RangeNon contact speed2.5~99999 RPM Contact speed0.5~19999 RPM Contact line speed (metric)0.05~1999.9 meter/min ResolutionNon contact speed0.1 RPM (2.5~999.9 RPM) 1 RPM (over 1000 RPM) Contact speed0.1 RPM (0.5~999.9 RPM) 1 RPM (over 1000 RPM) Contact line speed (metric)0.01 meter/min (0.05~99.99 meter/min) 0.1meter/min (more than 100meter/min) Accuracy (0.05% 1 Effective distance50~500mm Memory functionMaximum value, minimum value, last value (automatically store 96 groups of data) Sampling rate0.8 seconds (above 60 RPM) Low battery indication Working currentAbout 65mA Timing6MHZ quartz crystal Timing accuracy10x10 to the minus sixth power (0~50) Maximum display99999 Operation modeFree conversion 1 x 4 x Accessories 1 x User Manual 2 x Reflective Paper 1 x Black Bag 2 x Screw