GGG-C-613D, FEDERAL SPECIFICATION, COUNTERSINKS, AND COUNTERSINKS AND DRILLS (28 SEP 1973)

GGG-C-613D, FEDERAL SPECIFICATION, COUNTERSINKS, AND COUNTERSINKS AND DRILLS (28 SEP 1973)., This specification covers countersinks and combination countersinks and drills (center drill) for use in centering work pieces and countersinking holes.