Sturdy Cardboard Box: 12x9x4 shipping boxes are made of corrugated cardboard. They are sturdy boxes for business shipping and routine packing, moving, mailing, shipping and storage. Shipping Boxes for Packing: Fast-fold and easy to assemble, the 12x9x4 shipping box is universal and advantageous for Packaging. Mailing Box for Daily: 12x9x4 shipping boxes, packs of 25, meet your daily packing, moving, shipping, and mailing needs. Reusable Material: 12x9x4 Corrugated boxes have certain recoil effect that gives better protection for your mailing item. Mailer Boxes Sizes: Mailing boxes are about 12x9x4 inches and are great for shipping, mailing and storage. shipping boxes for small business