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 6140, DEPTH BASE ATTACHMENT, suitable for calipers with beam width (w) .630", 6928640303579
3M 76997, Scotch-Mount Indoor Double-Sided Mounting Tape 314H-MED-DC, 1 in x 125 in (2,54 cm x 3,17 m), 7100216168
3M 26325, PPS Series 2.0 Spray Cup System Kit, Large (28 fl oz, 850
mL), 125 Micron Filter, 7100134637
3M 87456, Silver Depressed Center Grinding Wheel, T27, 4 in x 1/4 in x 5/8 in, 7100141076, 20 per case 