... Back Light USB Interface Data Archive Capacity Ultrasonic hardness tester HRVB-31, mainly used in Rockwell hardness measurement, also can be ... It has the smallest indentation in portable hardness tester.Application:HRVB-31 portable ultrasonic hardness tester has leading technology, convenient, high precision ... /60Hz DC 6V7 Dimension:165×90×38mm8 Weight: 700g HRVB-31 Ultrasonic Hardness Tester