BoxYeah 50 Pack - Deluxe White Literature Mailers Shipping Boxes - 45 Sizes To Choose - Example (12 x 11 x 3) Feature protective side flaps and front outside tuck closure. Assembles in seconds without tape, glue or staples. Maximum protection for your most important documents. Manufactured from strong 200#/ECT32-B oyster white corrugated. Ships and stores flat to save space.