Feature: 1. 4 DIGIT LED: The digital tachometer adopts 0.56in LED 4 digit display, which is easy for observation and reading, and is convenient and practical. 2. WORKING RANGE: The speed measurement range is 5‑9999RPM, the frequency range is 0‑98990.1Hz, this tachometer has a wide range of applications. 3. MULTIPLE FUNCTIONS: Setting parameters will be memorized in case of power failure, with 10s reset time, which has high accuracy and stable performance. 4. EASY TO INSTALL: The 4 digit tachometer has a compact size, and adopts embedded installation, which is easy to install and takes up little space. 5. WIDE APPLICATION: This speed meter is suitable for detecting the rotational speed of various motors, widely used in household or industrial equipment. Specification: Item Type: Digital Tachometer Material: ABS Usage: Speed Measurement Display: 0.56in 4 digit LED Speed Range: 5-9999RPM Frequency Range: 0-98990.1Hz Rate Setting Range: 1-99 (Default: 01) Reset Time: 10s Refresh Time: 120-1200RPM: 0.2-0.5s; 2400-9999RPM: 0.25-0.6s Accuracy: 5000RPM: About 3RPM Input Signal: Voltage pulse signal, active contact signal, PNP, NPN Power Supply: DC 8-15V Installation: Embedded +12V: DC 8-15V input positive GDN: DC power negative Input+: Signal Input. Package List: 1 x Digital Tachometer 1 x Connection Cable Note: The user can set the appropriate rate to measure frequency less than 100KHz (999.9 x 99=98990.1Hz).