High Quality Self Sealing Mailers. Thicker and Stronger. You can feel the difference. UPS, FedEx & USPS APPROVED Superior tear and puncture resistance The dark inner layer provides confidentiality. Pressure sensitive adhesive provides a high strength durable closure, water and dirt resistant. Mailers are perfect for shipping a wide variety of non-fragile items. Water, Tear and Puncture resistant. Lightweight saves on postage. High strength seams allow for over-stuffing. Fast Shipping!