Features: 100% brand new and high quality 0.56 LED 4-digits display, clear and easy for readings. Rotate speed measuring range: 5-9999RPM; frequency range: 0-98990.1Hz. Mini size, high performance and fast reaction speed. Setting parameters will be memorized when power off. Suitable for detecting the speed of every kind of motors. Package Includes: 1 x Digital Tachometer Specifications: Display: 0.56in 4-digit LED Display Color: Blue / Green / Red (Optional) Rotate 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: Approx. 3RPM Input Signal: Voltage Pulse Signal, Active Contact Signal, PNP, NPN Power Supply: DC 8-15V Installation: Embedded Wiring: +12V: DC 8-15V Input Positive GDN: DC Power Negative IN+: Signal Input Panel Dimension: 72x 36x 20mm / 2.83 x1.42x 0.8in Item Weight: 25g / 0.88oz Tachometer Rate Setting Instructions: 1.Rate range: 1-99(default 01: display value is same with actual value; if the rate is 10, display value x10=actual value) 2. When power on, the meter display 0 3. Press SET button, display 1; press again, display 01 4. When display 1, is measuring RPM; press ADD, from 1 to 2, when display 2, is measuring frequency; display 01 is for rate setting, short press ADD for +1, long press for +10; 5. After setting the values, it will be stored if no operation in 10s, return the selected function interface; 6. With 1 decimal point, that is when rotate speed is 1000RPM. note: User can set the appropriate rate so as to measure frequency, less than 100KHz (999.9x99=98990.1Hz). The sensor is not included, this tachometer can not be used to test the car rotate speed separately. Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.