If you ship a lot of small, non-fragile items like clothing, stickers, documents, or lightweight products, these poly mailers are a must-have. Each bag is 5x7 inches (usable size below the flap), made from 2.5 mil thick virgin polyethylene plastic, so they're tough, waterproof, and tear-resistant. The self-seal adhesive strip makes packing a breeze—no tape needed, and once sealed, they're tamper-evident. The white opaque color with a silver/gray inner lining keeps contents private. A case of 500 means you're set for a long time, and the lightweight design saves on shipping costs. They're approved by major carriers like USPS, UPS, and FedEx. Just remember, these aren't padded, so use bubble mailers or boxes for fragile items. For t-shirts, accessories, paper goods, or small retail items, these mailers are reliable, professional, and super convenient.