Durable Poly Mailers: waterproof, tear-resistant shipping bags protect small items and apparel securely during transit; perfect for everyday business use (100-pack). Secure Self-Sealing Closure: These poly mailer envelopes feature a strong peel-and-seal adhesive strip, ensuring packages remain tamper-proof without additional tape. Cost-Effective Lightweight Packaging: Bulk 100-count lightweight plastic shipping bags reduce postage costs, ideal for small businesses, online sellers, and retail operations. Professional Appearance: Vibrant blue envelope mailers offer a clean, attractive presentation, enhancing your brand identity while maintaining customer privacy. Multipurpose Shipping Bags: Sized 10"x13", these mailer envelopes conveniently ship clothing, jewelry, cosmetics, accessories, and other small e-commerce products. 10x13 Poly Mailer