A one piece folder, often called a book wrap or a bookfold mailer, is a single die cut sheet of corrugated that folds around a flat product and locks itself shut. There is no glue and no separate lid. It is cheap, it ships flat, and it protects edges and corners better than a bag, which is why books, framed prints, documents and flat electronics all end up in one.
Two measurements, then the one everybody forgets
Start with the flat footprint: length and width of the product lying down, measured at the widest point including any wrap, sleeve or shrink film. Then measure the stack thickness. If you ship a single item, that is straightforward. If you ship anything from a thin paperback to a hardback, or one item up to four, you have a range rather than a number.
That range is the spec. A one piece folder handles varying thickness through multiple parallel scores on its side panels, so the wrap can be folded at a different crease depending on what is inside. The number of scores and the spacing between them are set in the die, so they have to be decided before tooling, not afterwards.
What to hand the supplier
| What to give | Example of a complete answer |
|---|---|
| Internal length and width | The flat footprint plus clearance, stated as internal |
| Thickness band | The thinnest and the thickest item you will actually wrap |
| Closure preference | Tuck and lock tabs, a peel and seal strip, or tape |
| Board | The flute, and whether print quality or stiffness matters more |
| Outside only, inside only, both, or plain kraft |
Where one piece folders go wrong
The two common failures both come from the thickness band. Set it too wide and a thin item rattles inside a folder creased for something thicker, which defeats the point of the format. Set it too narrow and your thickest SKU will not close, so the packer forces it and the locks tear. The fix is to look at what you ship by volume, not by catalogue, and design the band around the bulk of your orders.
The third failure is dimensional weight. A folder that is generously sized adds billable volume on every parcel. Check your carrier's current dimensional divisor and work out what an extra half inch of thickness costs you across a year of shipments.
Board and print
E flute gives a flat printable outside and enough stiffness for most book and print work. B flute adds rigidity and puncture resistance for heavier stacks. Kraft outer with no print is the cheapest route and it still protects; printing the inside panel is a low-cost way to make the unboxing feel considered without changing the structure.
Minimum, price and lead time
Minimum order is 100 units, from about $0.48 per unit at bulk volumes, confirmed on your written quote. Die and plates, design support, US shipping and a digital proof before anything prints are included, so cutting a folder to your exact footprint and thickness band costs no more to tool than a near-standard one. Lanes are Rush (expedited production plus air freight), Standard (air) and Cost saver (sea), with a floor of from about 7 business days, plus 2 to 5 for delivery. Specialty imported items can run up to about 12 weeks, and Rush adds about 7 to 25%, depending on the job.
Send the flat footprint and your thinnest and thickest item, and we will set the score range and quote it at /quote/. For the boxed alternative, see book box dimensions, and mailer boxes if the product is not flat.
