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 2724-S3E, BORE GAGE SET, .7-6", digital indicator range .5"/12.7mm, 6940561983715
Dynabrade 57404BK 2-3/4" W x 8" L Dynaline Sander, Central Vacuum
3M 00949, Scotch-Brite Clean and Strip Disc, CS-DC, SiC Extra Coarse, 6 in x 5/8 in, 7100054081 