... range 1.2~220mm 2.auto null point calibration,sound velocity measuring 3.data storage/inquiry ... Our products include laser distance meter,infrared thermometer, anemometer, sound level meter, noise meter, vibration meter, ultrasonic thickness gauge, film ... frequency5MHztubing measuring lower limitΦ20*3mm(steel)auto null point calibration, system error correctionlinear auto compensation, correct ...