MRC:
The specification,standard,or manufacturers reference,and the classification designation,such as class,condition,temper,and the like,that identifies the material.MDCL
Material Specification:
Qq-b-613, comp 1 federal specification 1st material response or qq-b-626, comp 1 federal specification 1st material response or qq-b-728, comp b federal specification 2nd material response or qq-w-321, comp 6 federal specification 2nd material response or qq-w-321, comp 7 federal specification 3rd material response