What We Like About This Mobile Roll File Few things are more annoying than not having an appropriate place to store your larger roll files. Since these tubes usually contain lots of documents, there is all the more reason they should be filed in an organized and secure manner. The angled top gives a simple solution to ordering your large files according to size. Roll file with four casters, great for wide diameter tubes * Heavy-duty frame with black powder coat and lipped bottom * 3/8-inch side bars for added support * Four rolling and locking casters * 12 compartments suit files up to 5.5 inches in diameter