Creates new styles, sets the current style, modifies styles, sets overrides on the current style, and compares styles.
List of Options
The following options are displayed.
Current Dimension Style
Displays the name of the dimension style that is current. The default dimension style is STANDARD. The current style is applied to dimensions you create.
Styles
Lists dimension styles in the drawing. The current style is highlighted. Right-click in the list to display a shortcut menu with options to set the current style, rename styles, and delete styles. You cannot delete a style that is current or in use in the current drawing.
The 
icon before the style name indicates that the style is annotative.
Unless you select Don't List Styles in Xrefs, dimension styles are displayed in externally referenced drawings using the syntax for externally referenced named objects. Although you cannot change, rename, or make current externally referenced dimension styles, you can create new styles based on them.
The item selected in List controls the dimension styles displayed.
List
Controls the display of styles in the Styles list. Select All Styles if you want to see all dimension styles in a drawing. Select Styles in Use if you want to see only the dimension styles currently used by dimensions in the drawing.
Don’t List Styles in Xrefs
When selected, suppresses display of dimension styles in externally referenced drawings in the Styles list.
Preview
Shows a graphic representation of the style selected in the Styles list.
Description
Describes the style selected in the Styles list relative to the current style. If the description is longer than the space provided, you can click in the pane and use arrow keys to scroll down.
Set Current
Sets the style selected under Styles to current. The current style is applied to dimensions you create.
New
Displays the Create New Dimension Style dialog box, in which you can define a new dimension style.
Modify
Displays the Modify Dimension Styles dialog box, in which you can modify dimension styles. Dialog box options are identical to those in the New Dimension Style dialog box.
Override
Displays the Override Current Style dialog box, in which you can set temporary overrides to dimension styles. Dialog box options are identical to those in the New Dimension Style dialog box. Overrides are displayed as unsaved changes under the dimension style in the Styles list.
Compare
Displays the Compare Dimension Styles dialog box, in which you can compare two dimension styles or list all the properties of one dimension style.