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 86803, Cubitron II Stikit Film Disc 775L, 120+, 5 in x NH, Linered w/Tab, Die 500X, 7100045865, 250 per case
Dynabrade 92208 1/8" W x 12" L 180 Grit A/O DynaCut Belt, 50/pack 
