Features: Pocket size Contact and photo ways Auto power off Data logging up to 100 groups Data hold and display back light Specifications: Measuring range and Resolution: 50-99.99RPM, 0.01RPM; 100-9999.9RPM, 0.1RPM; 10000-99999, 1RPM Accuracy: ¡À(0.03%¡À2d) Measuring distance: 50mm to 250mm (when the battery voltage is sufficient) Operating environment: Elevation: <2000m Relative humidity (RH): =<80%RH Operating temperature: 0 to 40 Degrees Centigrade Power supply: 4*1.5V AAA battery (not included) Dimension: 155*60*27mm SKU: X1IN10276 Package includes: 1 * MS6208B Digital Tachometer 1 * Reflective Sheeting 1 * User Manual