These 4 x 4 x 3 inch kraft corrugated mailers are built from ECT-32-B single wall corrugated board and use a one-piece fold-lock design that forms double walls on the front and sides without tape, glue, or staples — reducing pack-out steps at the fulfillment station.

The compact interior suits small hard goods, cosmetics, health products, and individually boxed components commonly shipped through e-commerce, specialty retail, and light manufacturing channels. The kraft finish is appropriate for both B2B distribution and direct-to-consumer fulfillment.

Each mailer ships and stores flat, minimizing warehouse staging space. Mailers weigh approximately 0.12 lbs each, adding negligible outbound weight. Sold in bundles of 50 and parcel-friendly.