"ISO 2768-2" refers to a part of the international standard ISO 2768, which deals with general tolerances for linear and angular dimensions. Specifically, ISO 2768-2 provides general tolerances for features without individual tolerance indications.

ISO 2768-2 defines for geometrical characteristics (plus a “fine” class for runout only):

This creates an economic advantage. By referencing ISO 2768-2, the designer acknowledges that the feature does not require a special, costly process to achieve perfection. If a feature requires tighter control than what Class H offers, the designer must then explicitly apply a specific GD&T frame to that feature. This dichotomy allows for cost-effective manufacturing: money is spent controlling only the features that truly matter, while the rest are left to the capable hands of general workshop accuracy.

The use of ISO 2768-2 offers several benefits:

ISO 2768-2 is titled “General tolerances — Part 2: Geometrical tolerances for features without individual tolerance indications.” Its primary function is to establish a standardized set of default tolerances for features that are not individually annotated. Without this standard, a drawing might need a tolerance callout for every single edge, surface, and profile, leading to "drawing pollution." By applying ISO 2768-2, the designer implicitly communicates that any feature lacking a specific geometric tolerance (such as flatness, straightness, or symmetry) need only meet the "general" standards of the specified tolerance class.