Used with standard outside micrometers with spindle .256″DIA to measure pitch diameter of screw threads.
Diameter accuracy: ?20_in. Cylindricity: 39_in.
Cylindricity: 1um. Hardness: HRC60.
Supplied with manufacturer inspection certificate.
Supplied with manufacturer inspection certificate.

Insize PHT-C751-S, 400 GRADE ABRASIVE PAPER, 6974029779886
3M 45179, Roloc Disc Pad TR, Medium 4 in 1/4-20 Internal, 7000045281 