What is this?Poly Mailers are mainly used to transport clothing and non-breakable items, such as T-shirts, jeans, shoes, and other clothing and accessories, as well as books, cosmetics or other small items.What will I get?Shipping Bags, we provide here, are in the size of:Material: PEColor: BlackBody Length:40cm/15.75 InchSize: 32x45cm/12.6×17.72 Inch(L*W)In the package of: 200 Pack x Shipping Envelopes BagsIs there any advantages of the product?1.Poly mailer bags made of PE material, waterproof and not easy to tear, sturdy and durable, and will not be damaged during long-term transportation, which can protect your items safely to their destination.2. There is strong self-adhesive tape at the seal of the plastic bag. To use, simply peel off the self-adhesive tape and fold over a plastic envelope to seal.