| Name | Description |
|---|---|
| Comments | Specific comments about the mullions. |
| Length | Maximum length of the mullion. For example, on a mitered mullion, the value is the pre-cut length. This is a read-only value. |
| Mark | Sets a label for the mullions. This value must be unique for each mullion in a project. Revit LT warns you if the number is already used but allows you to continue using it. (You can see the warning using the Review Warnings tool. See Reviewing Warning Messages.) |