... does not need protections. Unlike other Shipping Supplies, Poly Mailing Envelopes do not contain any bubble, foam or paper cushioning ... Mailers are less expenses than other Shipping Bags. Poly Mailing Bags also are lighter weight so they are less expensive ... used to ship clothes, bathing suits, shoes, books, magazines, etc. Plastic Mailing Envelopes come in a wide variety of thicknesses, colors, and ...