Stackable storage box offers Mystic Setup, amazingly fast, incredibly convenient, effortless assembly to store your letter-size and legal-size documents. The box arrives flat and pops up upon opening. All you have to do is press down on one side, and the box is ready for use. The Bankers Box Mystic Storage Box provides a sturdy container to protect your files with double-wall construction on all sides, the top and bottom. Superior stacking strength minimizes the need to re-box files. Locking lid keeps contents secure and makes box comfortable to carry. Consumer-preferred larger labeling area ensures easy file identification. Staple-free box prevents punctures and won't catch on clothing or shelving. Stacking strength is 750 lb. The interior dimensions are 12" wide x 15" deep x 10" high.