Feature: 1. Smart Testing: With 10-9999RPM wide measuring range as well as high testing accuracy, the motor tachometer is very useful. 2. Clear Display: Digital display of 4 digit red LED enables a clear viewing on the real time data, simplifying the operation. 3. Reliable Work: IP68 waterproof grade allows for stable working performance under various environments, also has Hall sensor. 4. Practical Use: Allows for wide application on ship, mechanical equipment, wind power machine, outdoor equipment, lathe, etc. 5. Easy to Install: Designed to have a light weight and a compact size, the installation can be quickly completed in minutes. Specification: Item Type: Motor Tachometer Working Voltage: DC 8V-24V Display Refreshing Rate: >3 times/second Display Mode: Red LED, 4 digits. Over Range Display: Below the measurement range, display LLLL. Beyond the measurement range, display HHHH. Measuring Range: 10-9999 Measurement Accuracy: ±0.1%, reading ±1 word. Waterproof Grade: IP68. Package List: 1 x Motor Tachometer1 x Hall Sensor1 x Accessory