Portable Hardness Tester for cast/rough surface parts/Economic Castings Portable Hardness Tester. Features. Loaded with features, this economically priced portable hardness tester is capable of measuring the surface hardness of a broad variety of metals on flat and round surfaces. Loaded with features, this economically priced portable hardness tester is capable of measuring the surface hardness of a broad variety of metals on flat and round surfaces. This portable hardness tester comes complete with the G impact device, calibrated HLG test block and rugged carry case. Designed to test large cast parts and those with rough surfaces: Example: part mass should be equivalent to 1 thick of solid steel where testing.