Feature: 1. 2 MEASURING WAYS: This tachometer has 2 measuring methods, contact and photoelectric non contact type, which are convenient for measuring photoelectric speed, contact line speed, etc. 2. CONTACT WHEEL: Using different rubber contact wheels can meet the precise measurement of contact speed for users in any situation, with a wide measurement range and high accuracy. 3. 4 CONTACT PROBES: This tachometer is equipped with 4 different contact probes to achieve close contact with the measured object, suitable for measuring conveyor belt, gear, pulley speed, etc. 4. LARGE LCD SCREEN: This digital tachometer is equipped with a large LCD display screen, which is clear and intuitive, ensuring fast and convenient readings, with a maximum display of 99999. 5. MEMORY FUNCTION: This tachometer supports maximum, minimum, and final values saving function without worrying about data loss due to low power consumption or accidental power outage. 6. APPLICABLE FIELDS: This tachometer can be widely used in manufacturing industries such as motor, fan, paper making, plastic, chemical fiber, washing machine, automobile, airplane, ship, etc. Specification: Item Type: Digital Tachometer Model: DT2236B Battery: 4 x 1.5V AA Battery (battery not included) Screen: 5 digit large LCD display, with a word height of 18mm Function: Wide measurement range and high accuracy. 10 new types of surface speed sensors, equipped with slots, can conveniently measure the speed and length of wires, cables, and ropes Range: Non Contact Speed: 2.5-99999rpm Contact Speed: 0.5-9999 rpm Contact Line Speed (Metric): 0.05-9999 meters per minute Resolution: Non Contact Speed: 0.1rpm (2.5-9999.9rpm); 1rpm (above 1000rpm) Contact Speed: 0.1rpm (0.5-999.9rpm); 1rpm (above 1000rpm) Contact Line Speed (Metric): 0.01 meters per minute (0.05-99.99 meters per minute); 0.1 meters per minute (over 100 meters per minute) Sampling Rate: 0.8 seconds (above 60 rpm) Low Battery Indication: Yes Working Current: 50mA Timing Accuracy: 0-50℃ Maximum Display: 99999 Operation Method: Free Conversion Accuracy: ±(0.05%+1) Effective Distance (Laser): 50-500mm Effective Distance (LED): 50-250mm Memory Function: Maximum, minimum, final value Size: Approx. 7.5 x 3.5 x 20cm / 3 x 1.4 x 7.9in. Package List: 1 x Tachometer4 x Accessories1 x User Manual2 x Reflective Paper1 x Black Bag