81 Piece Grade AS-0/2 Steel Gage Block Set ~ Each block has a threaded center hole. ~ Meets or exceeds U.S. Federal specification GGG – G – 15C. ~ Complete with manufacturer’s calibration or certification that is not NIST traceable. ~ Made of the highest quality tool steel. ~ Surface hardness is HRC 64. ~ Supplied in a sturdy fitted wooden case. ~ Accurate to +4/-2 millionth. Each block has a threaded center hole. Made of the highest quality tool steel. Surface hardness is HRC 64. Accurate to +4/-2 millionth. Supplied in a sturdy fitted wooden case.
