Postal approved poly mailers are our premium option for e-Commerce shippers since they are certified to meet US postal service requirements for shipping. Made from extremely strong 2.5 mil, fully-opaque, co-extruded LDPE, these lightweight protective envelopes are tamper-evident, tear-resistant, and water-resistant. They have a tear perforations for easy opening and an anti-static adhesive strip that prevents the mailers from sticking together in mass-packing operations. These mailers are ideal for mass packing operations and will help save in shipping costs due to their light weight. Value Plus Poly Mailers are the most economical option when it comes to shipping non-fragile items such as clothes, books, toys, documents and more. Made from an extremely strong 2 mil, fully-opaque, co-extruded LDPE, these lightweight protective envelopes are tamper-evident, tear-resistant, and water-resistant. They are the ideal package for covering and protecting items that aren't easily damaged in transit.