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″.
setting ring when supplied may be .20008″.

3M 64804, Scotch-Brite EXL Unitized Mounted Point, W163 x 1/8 in 8S FIN, 3M 7010300871
Standard Abrasives 877059, Unitized Mounted Point, 732 A3 x 1/4 in, 3M 7010310345
Dynabrade 94980 1/4" Composite-Style Coupler, 1/4" Male
Insize 2307-1R, REVERSE READING DIAL INDICATOR, 1", lug back, 6928640396649 