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 54135, Scotch-Brite Roloc AL Surface Conditioning Disc TR, 2 in x NH A VFN, 7100075708, 200 per case
Insize 4809, U.S. STAND SHEET METAL GAGE, 0-36(.3125~.0070"), 6928640330162
Dynabrade 94991 1/4" Female Composite-Style Coupler with 1/4" Female Plug Assembly
Dynabrade 94980 1/4" Composite-Style Coupler, 1/4" Male 