[100% SATISFACTION]Contact us first if you have any problems with our product or service. We will try our best to help. This unit is widely used in various precise measurement for different hardware / parts in industrial realm; one of its important application is to monitor the level of thickness-de-creasing during operation of various and pressure container. Ultrasonic Thickness Gauge GM100 1. Auto calibration to assure the accuracy. 2. Sound velocity measurement: with a given thickness to measure the sound velocity to improve accuracy. 3. Large LCD display for easy reading. 4. Low battery, auto power off function, etc. 5. Can used in the field or work at heights *Measurement range: 1.2~225mm * Accuracy: ± mm * Resolution: 0.1mm * Sound speed range: 1000~9999m/s *Working frequency: 5MHz * Lower limit of pipe measurement: Φ20*3mm * Automatic proofing zero point, can correct system error * Linear automatic compensation, using computer software to correct the probe nonlinearity error in the whole range to improve accuracy *Data storage / data query / data deletion function *Measure the speed of sound: directly measure the speed of sound according to the thickness of the sample block * Low power indication function *Automatic shutdown function *LCD backlight function *Power Supply3*1.5V AAA Batteries