This document discusses check dimensions in technical drawings. It states that dimensions related to function, safety, fit, or appearance must be marked as check dimensions. This allows quality control to only measure the critical check dimensions rather than every dimension, reducing inspection effort. The document then provides an example of a simple turntable assembly and identifies various dimensions as safety, clearance, or function critical that should be check dimensions. By designating these critical dimensions, the number of dimensions needing inspection is reduced from 21 to just 8.