HR-521 hardness testers have real-time electronic test-force control for precise and accurate loading. Scale selection from the brightly lit LCD touch screens automatically sets preliminary and total test forces, preventing selection errors. Automatic brake and automatic start functions make testing quick and simple. A continuous testing mode allows repetitive testing of same-height samples with just the push of a button. The testers offer data processing capability with 1,024 data point memory and automatic conversation to most hardness scales. They produce a clear view of the test area and allow testing of inside diameters down to 1.5 in. (40 mm), or 0.875 in. (22 mm) using special indenters.