Features Adopting advanced technologies to achieve contact or non-contact measurement of rotation speed and line speed. Speed sensor with groove measures speed and length of wire, cable and rope conveniently. Automatically store max value, min value and the last measurement value. Contact accessory and photoelectric accessory can be converted mutually at any time to achieve multi-purpose use.​ Automatically prompt when the voltage of power supply voltage is lower than the specified value.​ 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: SM6236EMeasuring Range:Photoelectric Tach: 2.5 ~ 99999RPMContact Tach: 0.5 ~ 19999RPMContact Line Speed: 0.05 ~ 1999.9m/minResolution: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 LCDAccuracy: ±(0.05%+1 digit)Sampling Time: 0.5 sec(over 60RPM)Range Selection: Auto-RangingMemory: Max. value, Min. value, Last value. 96 data storageTime Base: 6MHz Quartz CrystalDetecting Distance: 50 to 500mm (Laser)Battery: 3 x1.5V AA Batteries (NOT included)Power Consumption: about 50mAColor: BlackSize (L*W*H): 21*7.4*3.7cm / 8.27*2.91*1.46inWeight: Approx. 436g/15.4oz  Package list:1 * Tachometer1 * User Manual3 * Reflective Paper1 * Screw4 * Tach Accessories1 * Photoelectric Tach Head1 * 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