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″.
setting ring when supplied may be .20008″.

3M 71358, 641WY 1/4" X 24", 600 Mesh Diamond Cloth Belt, 7010534894
Insize 4120-11, METRIC THREAD RING GAGE, GO, M11x1.5, 6928640341465 