I am using these folders to store old tax files that were in manila folders in a file cabinet w/o side rails for the hanging files. I added the frames. Some files were 5" thick so needed many hanging folders to accommodate the paper when split into multiple folders. These hanging folders provided the cost vs performance I was looking for but learned that you don't slide them on the rails when heavy or the paper tears and the hooks bend a bit. Other than that they are working just fine!!