Features:1,Mea suring RPM is safe & accurate without attachment to object. 2,Wide measuring range & high resolution. 3,Digital display gives exact RPM with no guessing or errors. 4,Used the exclusive MICRO-COMPUTER LSI-circuit and crystal time base to offer the high accuracy measurement & fast measuring time. 5,The last Value/max. Value/min. Value will be automatically stored in memory and can be displayed by turn. 6,The use of durable, long-lasting components, including a strong, light weight ABS-plastic housing assures maintenance free performance for many years. The housing has been carefully shaped to fit comfortably in either hand. Tachometer(Photo/Touch Type) DT-2856 Product synopsis Model: DT2856 Measuring range: rotative velocity laser 2.5-99999r/min Contact 0.5-1999r/min Laser tach detecting distance: 50-600mm Accuracy: ¡À(0.05%n+1d) Resolution: 0.01/0.1/1 Memory: max/min/last value Power supply: 4x1.5V AA (UM-3) battery Battery indicator: low battery indicator Dimensions: 220x75x29mm Weight (not including probe):171g