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.

3M 65490, Pro Grade Precision Ultra Durable Universal Hole Sanding Disc, DUH580TRI-10T, 5 IN x UH, 80, 7100202914, 10 per pack 
