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 30137, Heavy Duty Canvas Wheel Masker, 20 inch, 7100145359, 4 per pack
Insize 2307-1R, REVERSE READING DIAL INDICATOR, 1", lug back, 6928640396649
3M 26003, PPS Series 2.0 Adapter, Type S2c, 16 mm Female, 1.5 mmThread, 7100135338
Dynabrade 15420 Dynafile III Abrasive Belt Tool
3M 76686, Cloth Belt 777F, 80 YF-weight, 2-1/2 in x 60 in, Film-lok, Single-flex, 7010359750, 50 per case 