HL200 portable ultrasonic hardness tester 1.Hardness Scale:HL,HB,HRB, ... ,HV,HS 2.Display:dot matrix LCD,128*64 dots HL200 portable ultrasonic Hardness testerTechnical Specifications:Error and repeatability of displayed ... :about 50 hours(With backlight off)Communication interface:USB1.1 HL200 portable ultrasonic hardness tester