Rockwell Hardness Meter TRHM-A10 - Rockwell Tester Labtron Rockwell Hardness Meter operates with a total test force range of 588 N to 1471 N with manual loading control. It features an analogue display with 0.5 HR resolution and supports specimens up to 170 mm height. Adjustable dwell time from 0 to 30 seconds suits hardness testing tasks.