Product Description Staples seaport blue letter/legal file box measures 10 7/8" x 13 7/8" x 18 1/4" and can accommodate both letter and legal files. Staples seaport blue letter/legal file box is constructed from polypropylene for added durability. The box measures 10 7/8" x 13 7/8" x 18 1/4 and features a snap-tight lid which keeps contents secure.