This is a package that combines 5 each of the two sizes of large Poly Mailers. (5) 24x21x6 Large Polymer Poly Mailer Expansion Envelopes and (5) 30x28x6 Extra Large Mailers, Package of 10. Condition is New. Shipped with USPS Priority Mail. These envelopes are great for mailing oversized, light weight items such as stuffed animals, linens, and diapers because they add virtually no weight to the shipping cost. These envelopes are difficult to purchase one at a time, as they are offered here.Strong polyethylene mailers protect products from moisture during shipping.Features gusseted side to allow for thicker items such as binders, books and catalogs. Puncture, moisture, tamper and tear resistant.High strength seams will keep contents intact even if over packed.The outer surface of the mailer is white and the inner lining is silver.Labels, ink and stamps adhere well.