Wide Measurement range from 15 RPM to 75,000 RPM. The last measured value is automatically stored in memory when the 'measure' button is released. Bright Red LED display with leading zero blanking gives the exact RPM. The battery consumption is very low. In Non-measure mode i.e. the measure button is released (memory ON), the battery consumption is still lower. This tachometer uses an advanced Micro Computer LSI Circuit with Quartz Crystal time base to give high accuracy and fast measurement. A high intensity RED LED for photo- tachometer gives a visible low current consumption beam. Unlike a filament bulb, an LED has almost infinite life. The use of a durable, strong ABS plastic housing assures maintenance free performance for many years. This housing fits comfortably in the palm of the user.