Press the button, the instrument can emit ultrasonic, when it encounters an obstruction, it gives feedback, then the instrument can display the actual distance. Features: 1. Accurately measure the vertical distance from a point to a certain surface with ultrasonic. 2. The internal temperature is automatically compensated and the measurement distance is not affected by the environment temperature. 3. The laser can be used to guide the measurement for more accurate measurement. 4. With automatic shutdown function. 5. It can be used to measure the length, width and height of a house, which is very convenient and practical. Suitable for construction, decoration, engineering, etc. 6. Made of high quality ultrasonic sensors Specification: Condition: 100% Brand New Item Type: Distance Measurer Material: Plastic Color: As Shown in the Picture Weight: Approx. 108g Measuring Range: 0.5-18.0m Accuracy: ± (1cm + 0.5% x distance) Power: 9V Battery (Not Included) Resolution: 1cm Power Consumption: 0.02W Temperature Compensation: 0-38°C Transmitting Frequency: 40KHz Function: Instantaneous or Continuous Measurement, Area and Volume Calculation, Laser Positioning Package List: 1 * Ultrasonic Distance Measurer Note: When measuring, the Distance Measurer body and the wall should be kept as vertical as possible. Especially when the measured distance is far, the more vertical, the higher accuracy of measurement data. Otherwise, the larger slope, the larger error. If not kept balanced, it will appear garbled. When measuring, It is better to hold the Distance Measurer with both hands so as to keep balance. 1、Accurately measure the vertical distance from a point to a certain surface with ultrasonic 2、The internal temperature is automatically compensated and the measurement distance is not affected by the environment temperature 3、The laser can be used to guide the measurement for more accurate measurement 4、With automatic shutdown function 5、It can be used to measure the length, width and height of a house, which is very convenient and practical. Suitable for construction, decoration, engineering, etc.