Corrugated board — flute profiles, liners and print for custom boxes
Corrugated board: the flute decides the strength, the liner decides the print.
A fluted paper core glued between two liners. E-flute for fine, printable mailers and product boxes; B-flute for heavier products; double wall where the board is the protection. Printed by flexo, litho-lamination or digital.
- Flutes
- E · B · EB double wall
- Liners
- Kraft · white · litho-lam
- Best for
- Mailers, product boxes, outers
What corrugated is
Strength from geometry, not from thickness.
Corrugated board gets its stiffness from a wave of fluted paper glued between two flat liners — the same principle as an I-beam. The flute profile sets the thickness and the cushioning; the liners set the surface and the print. The result is a board that is far stronger than its weight, which is why it is used for anything that has to travel or carry weight.
For custom packaging the choice is usually between E-flute — fine, thin, crisp to print, the mailer and product-box standard — and B-flute for heavier products. Double wall combines two flutes for products where the board itself is the protection. Liner choice then sets how it prints: natural kraft for flexo brand marks, white for full color, or a litho-printed sheet laminated on for carton-quality print.
- E-flute≈1.5mm
- B-flute≈3mm
- EB double wall≈6–7mm
Materials & finishing
Flute profiles and liners.
Specify the flute for the product's weight and journey, then the liner for the print.
Materials & finishes- E-flute≈1.5mmFine flute, crisp print. Mailers and product boxes.
- B-flute≈3mmHeavier products and outers.
- EB double wall≈6–7mmMaximum protection.
- Litho-laminatedPrinted sheetFull-color carton-quality face.
Print methods & finishes
- Flexographic 1–2 color
- Litho-laminated full color
- Digital full color
- Interior print
- Matte or gloss coating
- Spot UV (litho-lam)
- Foil stamping (litho-lam)
What corrugated is used for
Anything that travels or carries weight.
Mailer boxes
E-flute, printed inside and out.
Product boxes
Litho-laminated E-flute for electronics and kits.
Hamper & gift boxes
B-flute lid-and-base with dividers.
Display trays
Printed E-flute for counters and shelves.
Inserts
Die-cut dividers and cradles.
Retail-ready outers
Cases that open into shelf trays.
Compare
E-flute or B-flute?
| E-flute | B-flute | |
|---|---|---|
| Thickness | ≈1.5mm | ≈3mm |
| Crisp — fine flute shows less | Slight flute pattern under print | |
| Strength | Good for retail-weight products | More cushioning and stacking strength |
| Use | Mailers, product boxes, displays | Heavier products, outers, hampers |
Start a quote
Three answers is all it takes to open a job.
Structure, board and finishing come next — with our team, on the full quote form.
No account needed. Artwork and reference images can be attached on the next step.
Corrugated questions
Before you ask.
Anything not covered here, put it in the notes on your quote and we will answer it directly.
Ask on your quoteWhat is the difference between corrugated board and paperboard?
Corrugated has a fluted layer between two liners; paperboard is a single solid sheet. Corrugated is stronger and thicker; paperboard prints finer and folds tighter.
Which flute is best for a mailer box?
E-flute for most products — it prints sharply and is strong enough for parcel networks. B-flute for heavier orders.
Can corrugated be printed in full color?
Yes. A litho-printed sheet is laminated to the board (litho-lam), giving carton-quality print. Digital print is an alternative for shorter runs.
Is corrugated board recyclable?
Corrugated is one of the most widely recycled packaging materials. Coatings and laminations can affect local recyclability.
Resources
Guides on choosing board
How to choose the right packaging material for a custom box
SBS, kraft, corrugated or greyboard? The board decides how a box prints, feels, protects and costs. A practical guide to matching material to product.
Read the guideMailer boxes vs folding cartons: shelf packaging and courier packaging are different jobs
A mailer is built to travel; a folding carton is built for the shelf. Many brands need both. Here is how they differ and how to combine them.
Read the guide
Related packaging
Packaging made from corrugated.
Start here
Send us your dimensions. We’ll send back a box.
Or talk to a packaging specialist: (209) 444-0744