GL-HRD-150 Electric analog Rockwell Hardness Tester is very easy to use , dial direct reading,There is no human error except setting the zero point to the dial. Accuracy complies with ISO 6508-2 and ASTM E18 standards. Main Accessories ModelGL-HRD-150Big Flat test anvil1Small Flat test anvil1V-shaped test anvil1Diamond Cone Indenter1Tungsten Carbide Ball ( 1.588mm / 0.063in ) Indenter1Standard Rockwell Hardness Block5 Tags Rockwell hardness tester Dial rockwell hardness tester