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″.

Insize 2323-04, BORE GAGE FOR SMALL HOLES, .24-.4", 6928640329227
Dynabrade 79405 4" Dia. x 4" W x 3/4" Arbor Hole, Medium, NWN DynaBrite Finishing Flap Roll
3M 26295, Cloth Belt 341D, P120 X-weight, 2-1/2 in x 72 in, Film-lok, Single-flex, 7010361722, 50 per case 