Currently Revit doesn't support multiple selection in Material edition dialog, so when user wants to delete multiple materials, he/she has to select one, delete, then one again and again. It's really tedious and waste lots of time. This little tool will help you a lot when you want to delete multiple materials. Take a look at the vedio to see how to use:-)
Actually there are a couple of places have the same issue.
Please refer to the introduction here: http://www.revitapp.com/download_center.html
New version is available in APP Download.
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