PRINCIPLE-- Ultrasonic range finder uses the ultrasonic wave to the object to be measured, and then calculates the ultrasonic round trip time to determine the measured distanceEASY&CONVENIENT-- Handheld laser range finder, small size and easy to carryMEASURING DISTANCE-- The tools needed to quickly measure room and room area. Ultrasonic range finder can measure linear distances from 0.5M to 18M (1.5 feet - 60 feet)TECHNOLOGY-- The range finder uses laser technology to accurately sense and accurately measure distancesWIDE APPLICATION-- Measure current temperature, measure length, measure area, measure volume. Suitable for quick measurement of distance and surrounding area wear, home renovation, tools for quick measurement of room and room areaSpecification:Item Type: Range FinderMeasuring range: 0.5m to 18mMaximum measuring distance: 18 metersThe sum of the maximum distances: 180.00 metersMaximum calculation volume: 1800.0 cubic metersBattery type: 1 x 9V Battery(not included)Resolution: 0.01 metersOperating frequency: 40kHzOperating temperature: 0-50 Weight: Approx. 105gPackage List:1 Range Finder 1 User Manual