For zero setting of inside micrometers, three points internal micrometers and bore gages.
Deviation is the difference between the ordered size and the size marked on the setting ring when supplied.
For example, the ordered size is .2”, the size marked on the setting ring when supplied may be .20008″.

Norton 66261013403 - 3" X 1/2" Extra Coarse Grade Silicon Carbide Bear-Tex Rapid Strip TR Stripping Disc, 10 Each
3M 22409, Roloc Disc 361F, P120 XF-weight, TR, 1-1/2 in, Die R150S, 7000045103
3M 22407, Roloc Disc 361F, 80 YF-weight, TR, 1-1/2 in, Die R150S, 7000045099
Insize 4102-136, STEEL GAGE BLOCK SET, 36pcs, grade AS-1, 6928640329876
3M 26138, PPS Series 2.0 Adapter, Type S42, 3/8 Female R-Angle, 19Thread BSP, 7100135930 