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″.

Dynabrade 30429 Housing for Model 51306
Dynabrade 01894 Drop-In Motor
Dynabrade 98276 - 1/2" Male Coupler with 1/2" Female Plug Assembly
Dynabrade 89242 3-1/2" W x 15-1/2" L Medium NWN DynaBrite Premium Belt
Dynabrade 57113 Rotor/Vane Set
Dynabrade 81035 2" W x 60" L 120 Grit A/O DynaCut Belt, 10/pack
Dynabrade 11518 Rubber Drive Wheel
3M 76680, Cloth Belt 777F, 60 YF-weight, 2-1/2 in x 60 in, Film-lok, Single-flex, 7010299927, 50 per case 