HHIP Pro-Quality black-oxide pin gage set with Cert is Certified set. Supplied in a plastic, sturdy, dust-proof fitted case. Sizes marked on case for easy identification. Hardened to 60-62 RC. Black-oxide finish to 10 Micron or better. Class ZZ. OAL: 2". Product Specification: .0110-.250" Range; MINUS SET: (-)0.0002" (+)0.0000".