When you select a drafting standard (and its revision), the default settings for edge symbols are automatically adjusted to match that standard.
If necessary, you can customize these settings to suit your specific drafting requirements.
Because text and leader lines are the most commonly used objects in annotations, the AutoCAD Mechanical toolset provides a single configuration point (the Standard Settings dialog box) for defining their default properties. These are referred to as the primary settings.
In the Edge Settings dialog box, the text and leader properties default to “By NameOfCurrentDraftingStandard.” This means that when you modify the primary settings, edge symbols automatically inherit the updated values. If you do not want edge symbols to follow the primary settings, you can override them, for example, by specifying an explicit text height instead of using the standard-based default.