MRC:
The specification,standard,drawing,or similar instrument that specifies environmental and performance requirements or test conditions under which an item is tested and establishes acceptable limits within which the item must conform identified by an alphabetic and/or numeric reference number. includes the commercial and government entity (cage) code of the entity controlling the instrument.TEST
Test Data Document:
81349-mil-n-21945 specification (includes engineering type bulletins, brochures, etc., that reflect specification type data in specification format; excludes commercial catalogs, industry directories, and similar trade publications, reflecting general type data on certain environmental and performance requirements and test conditions that are shown as "typical", "average", "", etc.).
MRC:
A feature of the item of supply which must be specifically recorded when the reference number covers a range of items.ZZZY
Reference Number Differentiating Characteristics:
As differentiated by special features, test data document
