The Standard Mobile Tub File with Lock is a file storage tub that accommodates letter-size hanging files. The office cart is furnished with a durable steel construction. Provides protection for files with a sliding locking lid with two keys included. The tub file includes additional file rails to support legal-size files. Mobile cart rolls on four wheels (two locking). Ships fully assembled except wheels. Letter Size. Material(s): Steel; Overall Material Type: Metal; Color(s): Black; Color Family: Black.