It was primarily used in general mechanical engineering, engine construction, and aerospace for components requiring precision assembly. Current Status
: Defines the manufacture and testing of limit gauges.
Designing plug gauges and inspection tools that verify if a hole meets the required specifications.
is a historical German technical standard that specifies ISO deviations for internal dimensions (holes) for nominal sizes ranging from 1 mm to 500 mm . Published in August 1965, it defines the fundamental tolerances and limit deviations—such as H7, H8, and G7—required for precision engineering and manufacturing. Understanding "DIN 7161 PDF Extra Quality"