The flute profile decides what a box can carry. A large flute gives stacking strength, a fine flute gives print quality, and double wall combines the two.
Look inside the board
Pick a flute type, then tap the layers of the cross-section to see what each one does.
Outer linerThe outer surface that takes the print: kraft, white or testliner.
Fluting (medium)Paper shaped into flutes by passing it through corrugating rolls with heat and steam; this middle layer gives the board its vertical and flat strength.
Middle linerThe flat paper that separates the two flutes in double wall board.
Inner linerThe inside surface that faces the product.
· Tap the layers
C
C (Large)
Flute / board height (mm)
3,2 – 4,0
Pitch (mm)
6,8 – 8,0
Ply
3
With a taller flute profile than B, C flute performs best for vertical load (ECT) and stacking strength (BCT). Its thicker wall gives strong cushioning against impact. It is used with confidence for medium-heavy industrial, agricultural and textile products, where the box itself must carry load during transport and storage.
B
B (Fine)
Flute / board height (mm)
2,2 – 3,0
Pitch (mm)
4,8 – 6,5
Ply
3
The standard flute profile and the most widely used in the corrugated industry. Its tight flutes resist surface crushing and puncture well. It gives clean results in die-cut box designs and in folding and creasing. Flexo print quality on B flute is very good, making it ideal for self-supporting products, especially food and fast-moving consumer goods.
E
E (Micro)
Flute / board height (mm)
1,1 – 1,8
Pitch (mm)
3,0 – 3,5
Ply
3
The finest flute profile: with many flutes per metre it resists flat crush (FCT) extremely well. Its smooth, tight surface gives the best print quality of all flute types. Light and attractive, it is chosen for small boxes, display packaging and offset litho-lamination, as a strong alternative to folding carton.
Double wall corrugated board
A high-strength 5-layer structure: two fluting layers bonded between inner, outer and middle liners with special starch-based adhesives.
BC
BC (Double Wall)
Flute / board height (mm)
5,5 – 7,0
Pitch (mm)
B: 4,8–6,5 / C: 6,8–8,0
Ply
5
The standard double-wall board in the highest strength class, made of 5 paper layers by combining B and C flutes. It brings together the high stacking strength of C flute and the crush resistance of B flute. It gives maximum protection for heavy industrial goods, export shipments, long-term storage and tough logistics.
EB
EB (Micro Double Wall)
Flute / board height (mm)
3,5 – 4,8
Pitch (mm)
E: 3,0–3,5 / B: 4,8–6,5
Ply
5
A double-wall (micro double) board of five paper layers, made by combining E and B flutes. It joins the smooth print surface of the outer E flute with the strength and shock absorption of the inner B flute. An excellent choice for delicate, fragile or heavy products that need both strong shelf appeal and superior protection.
EB
EB Single-Face (4-Ply)
Flute / board height (mm)
3,5 – 4,5
Pitch (mm)
E: 3,0–3,5 / B: 4,8–6,5
Ply
4
A special 4-ply corrugated board combining B and E flutes, with the outer fluting left uncovered. It is made specifically so that high-resolution offset-printed board can be laminated onto the top surface. It is chosen for premium consumer and display packaging that also needs high strength.
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