Expandable Mailer
Ships and stores flat. Expands around the product at the pack station. No outer box needed.
What it is
A poly mailer with a self-expanding foam insulation layer. It arrives and stores flat, then expands at the pack station into a snug, form-fitting enclosure around the product. Standard gel packs cool a smaller space more efficiently because there's less air to chill.
Why teams switch from EPS coolers
- 87% less storage space than EPS cooler boxes, because it ships and stores flat.
- No outer carton. Approved by UPS, USPS and FedEx as a shipping container on its own, so there's no box, void fill or kitting step.
- Smaller parcels. A compact envelope ships smaller than a bulky cooler, which lowers dimensional weight.
Good for
Vials and pens for peptide and GLP-1 shipments, chocolate and confectionery, and temperature-sensitive skincare. Choose the 1⅜" wall for longer or hotter lanes; we spec the wall and refrigerant to your lane before you order.
Sizes and specs
| Size | Wall | Units per case |
|---|---|---|
| 9 × 11 in | 1" | 72 |
| 9 × 11 in | 1⅜" | 72 |
| 12 × 14 in | 1" | 48 |
| 12 × 14 in | 1⅜" | 48 |
| 14 × 18 in | 1" | 24 |
| 14 × 18 in | 1⅜" | 24 |
Questions
How long does the expandable mailer keep product cold?
Thermal protection for 24–48 hours, depending on size, wall, refrigerant and season. Choose the 1⅜" wall for longer or hotter lanes. ISTA 7E validation is available for your exact pack-out.
Does it need an outer box?
No. UPS, USPS and FedEx approve it as a shipping container without an outer corrugated carton.
What is the minimum order?
One case: 72 mailers for 9×11, 48 for 12×14, or 24 for 14×18.
How much storage space does it save?
It ships and stores flat and takes 87% less storage space than EPS cooler boxes.
Related products.
Ready to spec your pack-out?
A written quote with spec, price and lead time within one business day.