Economy file is designed for letter-size hanging folders (sold separately) Design features a sliding cover, keylock to secure files, piano-hinge top and shelf storage on bottom All units are keyed alike Economy file is designed for letter-size hanging folders (sold separately) Design features a sliding cover, key lock to secure files, piano-hinge top and shelf storage on bottom Economy file is designed for letter-size hanging folders (sold separately). Design features a sliding cover, keylock to secure files, piano-hinge top and shelf storage on bottom. All units are keyed alike. Mobile file has four dual-wheel casters for easy mobility. All units are keyed alike