Step #155 in the Expanded Vanilla list
Featured In Mod Lists:
Total Overhaul (#275), Graphics Overhaul (#207), Expanded Vanilla (#155), I Heart Vanilla (#18), I Heart Vanilla: Director's Cut (#22), Legacy Graphics Overhaul (#201), Legacy Total Overhaul (#268), Legacy Expanded Vanilla (#131)
This tool is absolutely essential if you use a mod that deals with leveled lists, which is very common. If you don't know what that is, and you use more than a handful of mods with plugins, it is probably worthwhile to use this.
This link should have everything you need to know.