Presto instant assembly - just push corners together and the box is ready for use! Heavy-duty, double end, double side, double bottom construction for stacking. Reinforced, tear-resistant handles make box comfortable to carry. Deep, locking lift-off lid stays in place for secure file storage. Box Type: Stackable File Storage; Box Style: Presto™ Instant Assembly; Strength: Heavy-Duty; File Size Format: Letter.