Features Advanced Technology: This digital tachometer uses advanced technology to enable contact or non-contact measurement of rotational speed and linear velocity. Grooved Design: The grooved speed sensor conveniently measures the speed and length of wires, cables and ropes. Contact accessories and optoelectronic accessories can be converted to each other at any time, realizing multi-purpose of one machine. Humanized Design: This digital tachometer adopts humanized design and has the function of automatically storing the maximum value, minimum value and the last measured value, and automatically prompts when the power supply voltage is lower than the specified value. LCD Digital Display: This speed test meter uses a large LCD display with backlight, and the reading is clear, even in the dark environment, it will not affect the data reading. Wide measurement range and high resolution. Intimate Service: We provide 7-day worry-free return and exchange service for all customers. If you have any questions about our digital tachometer, you are welcome to contact us and we will serve you wholeheartedly. This item adopts the microcomputer (CPU) technique and junction laser technique for one instrument which combines Photo Tach (RPM) and Contact Tach (RPM, m/min). Specification: Model: SM6236E Measuring Range: Photoelectric Tach: 2.5 ~ 99999RPM Contact Tach: 0.5 ~ 19999RPM Contact Line Speed: 0.05 ~ 1999.9m/min Resolution: Photoelectric Tach: 0.1RPM (2.5 ~ 999.9RPM), 1RPM(over 1000RPM) Contact Tach: 0.1RPM(0.5 ~ 999.9RPM), 1RPM(over 1,000RPM) Contact Line Speed: 0.01m/min(0.05 ~ 99.99m/min), 0.1m/min(over 100m/min) Display: 5 digits 18mm backlight LCD Accuracy: ±(0.05%+1 digit) Sampling Time: 0.5 sec(over 60RPM) Range Selection: Auto-Ranging Memory: Max. value, Min. value, Last value. 96 data storage Time Base: 6MHz Quartz Crystal Detecting Distance: 50 to 500mm (Laser) Battery: 3 x1.5V AA Batteries (NOT included) Power Consumption: about 50mA Color: Black Size (L*W*H): 21*7.4*3.7cm / 8.27*2.91*1.46in Weight: Approx. 436g/15.4oz    Package list: 1 * Tachometer 1 * User Manual 3 * Reflective Paper 1 * Screw 4 * Tach Accessories 1 * Photoelectric Tach Head 1 * Storage Case   Note: 1. Due to the difference between monitors and light effect, the pictures may not reflect  the actual color of the item. 2. Please allow slight error due to manual measurement. Thanks for your understanding. Package List