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″.

Dynabrade 56815 5" Dia. Non-Vacuum Dynorbital Supreme Random Orbital Sander, 3/16 Orbit
Dynabrade 01907 Housing for Model 52431
3M 80800, Scotch-Brite Roloc+ Combi-R Wheel, 2-1/2 in x 1-1/4 in P180 X-weight, 7000077959, 10 per case 