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″.

Dynabrade 78579 1/4" Dia. x 1" W x 1/8" Center Hole, 60 Grit, 100/pack
Norton 66261127733 - 2" X 50 Yard 60 Grit Metalite™ Aluminum Oxide Cloth Roll, 1 Each
Insize 1179-300, DIGITAL RTJ RING GROOVE CALIPER, inside diameter of RTJ ring groove .4-12"/10-300mm, outside diameter of RTJ ring groove 1-12"/25-300mm, 6928640302565 