Large measurement range (from 2.5 to 99999 rpm) and high resolution (from 0.1 to 1 or 1 rpm). Automatically record the MAX. value, Min. Value and Last value with low battery indication. Capable of measuring at a distance of 2-20in (50-500mm) with large LCD display. 0.8 Second time sample rate and 5-digit 18mm LCD display with non-contact RPM measurement. Non-contact digital photo tachometer with stable performance. Wide usage: usually can be employed in the field of engine, wheel, lathe for metal or wood cutting work, fan electrical, paper making, plastic industry, chemical fiber, washing machines etc. DT-2234C+ Non-contact LCD Digital Tachometer 2.5-99,999 RPM Meter Tester Display5 digits and 18mm (0.7 inch) LCD screen Measuring range2.5 RPM-99,999 RPM Resolution0.1 RPM at 2.5-999.9 RPM, 1 RPM at 1000-99,999 RPM Accuracy (0.05% + 1 digits) Measuring distance50-500mm / 2-20in Time base 6 MHz quartz crystal oscillator Sampling time0.8 s (more than 60 RPM) Power supply1 * 9 V 6F22 battery (Not included) Power consumptionapprox. 30mA Working temperature0~50 (32~122) Size130 * 68 * 26mm / 5.1 * 2.7 * 1.0in It is a portable digital touch-free tachometer with stable performance. Wide measuring range from 2.5 RPM to 99999 RPM and high resolution of 0.1 RPM or 1 RPM. High sampling frequency , clear LCD screen, high measuring precision. This tachometer can automatically record the maximum value, the minimum value and the last value. With automatic range, low battery indication and other functions . Wide use in the field of motor, wheels, lathe, electric fan, paper making, plastic industry, washing machines, car making, etc.