Non-contact MeasurementBased on embedded MCU, optoelectronic technology and semiconductor technology, this tachometer realizes accurate non-contact measurement. Switchable Measurement ModesManual / Automatic mode optional, meeting various requirements. Adjustable power (high / low), adapting the far / near distance requirement to protect user' s eyes. Automatic RecordAutomatically recording 50 sets of data, and the sampling interval time could be reset to meet different needs. Additional FeaturesAutomatic shutdown in 30 seconds without operation. Capable of recording the maximum, minimum and average values. LCD Display5-digit LCD clear display with backlight, 99999 maximum reading, not dazzling in grey font, visible in low luminance environment. Features: [Compact Size] Easy to carry, convenient to operate and durable to use. [LCD Display] 5-digit LCD clear display with backlight, 99999 maximum reading, not dazzling in grey font, visible in low luminance environment. [Non-contact Measurement] Based on embedded MCU, optoelectronic technology and semiconductor technology, this tachometer realizes accurate non-contact measurement. [Switchable Measurement Modes] Manual / Automatic mode optional, meeting various requirements. [Automatic Record] Automatically recording 50 sets of data, and the sampling interval time could be reset to meet different needs. [Automatic Shutdown] Automatic shutdown in 30 seconds without operation. [Additional Features] Capable of recording the maximum, minimum and average values. Specifications: Material: ABS Color: Grey Power Supply: 2 * AAA battery (NOT included) Power Consumption: 25mA (low power), 40mA (high power) Operating Temperature: 0~50 Storage Temperature: -20~60 Display: 5-digit LCD, Max. 99999 Available Distance: 50mm~500mm Sample Time: 0.5s (over 120RPM) Measuring Range: 2.5RPM~99999RPM Resolution: 0.1RPM (2.5RPM~999.9RPM), 1RPM (1000RPM~99999RPM) Accuracy: 0.05%rdg + 1digtal Item Size: Approx. 11*6*2.5cm / 4.33*2.36*0.98in Item Weight: Approx. 72g / 2.54oz Package Size: Approx. 19.3*12.5*4.5cm / 7.6*4.92*1.77in Package Weight: Approx. 143g / 5.04oz Note: Please read the Users Manual before use. Packing List: 1 * Digital Tachometer 3 * Reflecting Tape Mark 1 * Users Manual(English)