The crystalfile extra foolscap file is made from durable polypropylene that lasts up to five times longer than regular manilla files the steel runners are engineered to take more weight than a standard suspension file for reliable effective use this pack of 25 black files comes complete with tabs and printable inserts for easy labelling of your contents extra strong suspension files for durable filing polypropylene lasts up to 5 times longer than manilla extra strong colour coded steel run