Bankers Box Heavy-duty Portable File Box provides organized and secure, waterproof storage and transport of letter-size documents. Durable plastic (polypropylene) construction features reinforced corners for added strength so the file box can stack up to five high. Modular design of the TAA-compliant file box means easy stackability. Comfortable handles allow easy lifting. The latching lid with handy organizer compartment ensures secure transport. Built-in hanging rail keeps files organized and accessible. Inside dimensions are 6-3/4" x 11-3/4" x 10-3/4".