IRHD (International Rubber Hardness Degrees) hardness testers provide highly repeatable hardness measurements on rubber and rubber components. The IRHD rubber testing method employs an initial test load that is applied to the specimen via an indenter. At this indentation position, the test is zeroed and the force is applied. The distance between the two applied forces are measured and translated to an IRHD hardness value. Checkline Europe offers a micro IRHD hardness tester for hardness measurement of samples between 1 and 5 mm and a macro IRHD hardness tester for samples with a minimal thickness of 6 mm.