Envelope measures 10.5 x 13.9″ overall, with an interior usable area of 9.5 x 12.5″ (#4) Made from kraft paper with a bubble-lined, water-resistant construction Lightweight design helps keep package weight lower for mailing Self-sealing peel-and-close flap makes packing fast and simple Includes 3/16″ slip bubble cushioning to support easier loading of items