HRMS-45 Digital superficial Rockwell hardness tester is equipped with a newly-designed large displaying screen with good reliability, excellent operation and easy watching, thus it is a high-tech product combining the mechanic and electric features. It can show and set the present scale, test force, test indenter, dwell time and hardness conversion; the main function is as follows: Selection of all the superficial Rockwell scales; Conversion scales of different kinds of hardness; Test results can be saved and printed out, automatic calculation of maximum, minimum and average value; With RS232 interface for connecting to the computer.