Feature: 1. Photoelectric and Contact 2 in 1: This digital tachometer integrates 2 measurement methods, contact and photoelectric non contact. The tachometer can perform photoelectric speed measurement, light source flicker frequency measurement, contact speed measurement and contact line speed measurement. 2. Accurate: The digital tachometer is made with different rubber contact wheels, which can meet the user's precise measurement of contact speed in any situation. 3. Contact Measurement: The tachometer is equipped with 4 different contact probes, which can be matched with suitable probes according to different scenarios to realize close contact with the measured object. 4. Clear and Easy to Read LCD Display: Our digital tachometer is equipped with a large LCD display for clear readings and is suitable for measuring the speed of conveyor belts, gears, pulleys, etc. 5. Widely Used: The RPM tachometer can be widely used in the manufacturing industries of motors, fans, paper, plastics, chemical fibers, washing machines, automobiles, airplanes, ships and so on. Specification: Item Type: Photoelectric Tachometer Material: ABS Display: 5 Digits 18mm Character Height, Yellow Green Backlighting Test Range: Photoelectric RPM: 2.5-99999 RPM Contact RPM: 0.5-1999999 RPM Contact Line Speed (Metric) 0.05-1999.9 Meters/Minute Data Accumulation Range: 1-99999 Resolution: (Optical) 0.1RPM (RPM) (2.5-999.9RPM), 1RPM (RPM) (1000RPM Or More) (RPM) 0.5-999.9 RPM, 0.1 RPM. 1000 RPM Or More, 1 RPM (Line Speed) 0.05-99.99 M/Min, 0.01 M/Min. 100 M/Min Or More, 0.1 M/Min Measurement Accuracy: (0.05% + 1 Word) Memory: Automatically Memorize The Maximum Value, Minimum Value, Last Measured Value; Automatically Store 96 Groups Of Data Sampling Time: 0.8 Seconds (Above 60 RPM) Effective Measuring Distance: 50mm- 500mm (Light Source) Time Base: 6MHz Quartz Crystal Oscillator Timing Accuracy: 10x10^-6(0-50) Range Selection: Automatic Switching Maximum Display: 999999 Power Supply: 4x1.5V AA Battery (Shipped Without Battery) Or External DC 6V DC Regulated Power Supply Power Consumption: 65mA Size(With Connector): Approx. 210 x 74 x 37mm / 8.3 x 2.9 x 1.5in Memory: Automatically Memorize The Maximum Value, Minimum Value, The Last Measured Value, Up To 96 Groups Of Measurement Data Storage Capacity. Package List: 1 x Tachometer4 x Connector1 x Instruction Manual1 x Storage Box2 x Screw