Navigate to the Item Revisions window from one of the following windows:
i.Master Items Summary folder or Master Item window
ii. Organization Items Summary folder or Organization Item window
iii. Bills of Material window
iv. Engineering Change Orders window

You can use letters, numbers, and characters (such as *, &, and #) to label revisions. Letters are always in upper case and numbers may include decimals. To ensure that revisions sort properly, decimals should always be followed by a number. Valid revisions can include: A, B, 01, 02, A1, B1, 1A, 1B, 0.0, 0.1, A.0, A.1, and so on.

Revisions are sorted according to ASCII rules. Each revision must be greater than the previous revision. Therefore, you cannot use revision 10 after revision 9 because, according to ASCII sorting, 10 precedes 9.
The value you entered in the Starting Revision field in the Organization Parameters window displays as the starting revision for the item. For revisions that have the same effective date, the revisions sort in descending order starting with the last revision you entered.