Custom poly mailers — 500-unit minimum.

A poly mailer is a flat plastic envelope for shipping. It is the cheapest and lightest way to send anything soft — apparel, textiles, accessories, samples — because it weighs almost nothing, takes no space in storage, and keeps the contents dry.

Unlike a box, a poly mailer gives no structural protection, so it suits goods that can be folded and will not crush. It is the default for apparel and e-commerce orders, and it is the reason a t-shirt can ship for a fraction of the cost of a boxed parcel.

Poly mailers are simpler than most packaging — the differences are in the closure and the printing.

• Self-seal mailers — a peel-and-stick strip along the lip. The e-commerce standard.
• Lip-and-tape mailers — a plain lip closed with tape, cheaper in volume.
• Printed mailers — your artwork on one or both sides; the whole surface is the brand.
• Tear-strip mailers — a perforated strip so the customer opens it without scissors.
• Recycled-content mailers — made with post-consumer resin.
• Compostable mailers — a paper or biopolymer alternative where plastic is not acceptable.

Most poly mailers are co-extruded film — usually LDPE, sometimes HDPE for a crisper feel — with an adhesive strip and a release liner. The gauge is chosen for the load: a light mailer carries a folded shirt, a heavier one denim or shoes.

Printing is flexographic, in one or more colors. The surface can be matte or gloss, opaque, translucent or white. Where a brand needs to move away from plastic, paper mailers and padded mailers do the same job in a different material.