These #4 kraft self-seal padded mailers measure 9 3/8 x 13 1/4 inches interior and combine a kraft outer shell with interior fiber padding that expands on contact to absorb shock during transit — eliminating the need for supplemental cushioning materials inside the envelope.

E-commerce shippers, warehouse fulfillment operations, retail distributors, and document mailers rely on this size for flat or lightly padded items including paperback books, apparel, electronics accessories, and multi-page documents. The #4 footprint accommodates standard letter-plus and A4-plus content without excess material waste.

The peel-and-seal closure uses a natural rubber adhesive that creates a secure, tamper-evident bond without tape or additional equipment. Mailers ship and store flat. Cases contain 100 units and ship via parcel carrier.