You can add a prefix, basic prefix, postfix, basic postfix, subfix, and superfix to the dimension text. Special characters can be added to fix text via the corresponding style table. You can also store text in these tables for future use.
To add a new fix text,
1. Click Annotation and then, in the Annotate group, click the arrow next to Linear or Circular. You can also click Angular in the Annotate group.
2. Click the appropriate linear or circular dimension
Dimension types under Linear or Circular respectively. The respective dialog box for the linear, circular, or angular dimension opens.
3. Type the fix text in the appropriate box (Prefix, Postfix, Superfix, and Subfix).
Basic prefix and Basic postfix are available only if you select a basic tolerance.
4. Complete the dimensioning operation.
To add special characters to the text,
1. Click Annotation and then, in the Annotate group, click the arrow next to Linear or Circular. You can also click Angular in the Annotate group.
2. Click the appropriate linear or circular dimension
Dimension types under Linear or Circular respectively. The respective dialog box for the linear, circular, or angular dimension opens.
3. Click the relevant fix button (Prefix, Postfix, Superfix, and Subfix) on the dialog box to open the Text Editor the corresponding style table. For example, click the Prefix button on the Single Dimension dialog box to open the Text Editor and the Prefix table.
4. Click Spec Chars on the table to open the Special Characters table.
5. Select the required character and click Apply, or double-click the character. Pin open the table to select more than one character.
The character metaname (or code) appears in the fix box.
6. Continue typing text or continue the dimension operation.
To clear a fix text,
Clear the check button corresponding to the unwanted text. The text is removed from the corresponding fix box. You can store fix texts in a table for later use.
Limitations
Old dialogs used to modify dimension fix texts, such as AM_DIM_ADD_FIXTEXT, will ruin the format of thread dimensions.
Linear or 
Circular. You can also click 
Angular in the Annotate group.