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″.

3M 08880 Scotch-Brite Surface Conditioning Belt, 3 in x 24 in, A CRS, 7000120598
Dynabrade 98270 1/2" Male Coupler
Dynabrade 94993 1/4" Male Composite-Style Coupler with 1/4" Female Plug Assembly
Dynabrade 96576 Tune-Up Kit for .3 hp Extreme Dynorbital Sander
3M 77255 SCOTCH-BRITE DURABLE FLEX BELT, 3/8 IN X 13 IN, A FIN, 7010410433
Insize 4808, WIRE GAGE, 0-36(.3249~.0050"), 6928640330155
3M 87153, Cubitron II Depressed Center Grinding Wheel, T27 Quick Change, 9 in x 1/4 in x 5/8-11 in, 7100103313, 20 per case
3M 94700, Cubitron ll Cloth Belt 947A, 60+ X-weight, 1/4 in x 24 in, Fabri-lok, Single-flex, 7010360589, 200 per case 