These 9 x 12 inch polyethylene mailers are built to 2.5 mil thickness, delivering reliable puncture, tear, and moisture resistance in a lightweight, flexible format. The self-seal adhesive strip forms a tamper-evident closure without additional tape or equipment, keeping high-throughput lines moving efficiently.

The white exterior accepts shipping labels, ink, and stamps directly without slipping, supporting clean, professional presentation at scale. E-commerce retailers, subscription box operations, apparel distributors, and retail fulfillment centers rely on this mailer size for soft goods, documents, and flat semi-rigid items that do not require a rigid outer shell.

Constructed with high-strength seams that hold integrity even when contents press against the envelope walls, these mailers combine durability with low per-unit weight. Each case contains 1,000 mailers and ships via parcel carrier.