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″. 
Related products
Measuring/ Inspection Instruments
Insize 4120-11, METRIC THREAD RING GAGE, GO, M11x1.5, 6928640341465
	$64.55
	
			
		Measuring/ Inspection Instruments
Insize 4120-10, METRIC THREAD RING GAGE, GO, M10x1.5, 6928640341458
	$64.03
	
			
		Measuring/ Inspection Instruments
Insize 4120-10N, METRIC THREAD RING GAGE, NO GO, M10x1.5, 6928640341762
	$53.29
	
			
		
Dynabrade 52574 4" (102 mm) Dia. Straight-Line Cut-Off Wheel Tool, Rear Exhaust, 1 HP, 18,000 RPM, 3/8"-24 Spindle						
Norton 66261014792 - 2" Medium Grade Aluminum Oxide Bear-Tex Speed-Lok High Strength Maroon TR Non-Woven Abrasive Disc 160 Each						
Dynabrade 78709 3/8" x 3/4"-B52 Dynacut A/O Mounted Point, Vitrified, 5/pack						
Insize 4120-14N, METRIC THREAD RING GAGE, NO GO, M14x2, 6928640341793						