Corrugated Flute Types: From A to N

A-flute has relatively large flutes that provide excellent cushioning and rigidity. You’ll mostly find A-flute combined with K-flute or C-flute. In Europe, however, A-flute is rarely used nowadays. While it’s strong and impact-resistant, it’s also more expensive due to its high flute factor (the ratio between flute height and length). For that reason, C-flute has largely replaced it.

C-flute offers a good balance between cushioning and strength. As mentioned, C-flute is commonly used as a replacement for A-flute. It’s more economical but still highly resilient. C-flute has about 140 flutes per meter and is considered a medium flute. In double-wall applications, it’s often combined with B-flute — the most common and reliable combination.

Bought a new TV lately? The box it came in was probably made from E-flute. This relatively new type of corrugated cardboard is often used as an alternative to solid board. E-flute has about 300 flutes per meter and a height of around 1.2 mm. It’s ideal for packaging single, high-value items. Not just because of its strength, but also because it delivers excellent print quality for logos, images, and text.

F-flute features up to 600 flutes per meter, what the packaging industry calls microflute. With a flute height of only about 0.8 mm (compared to roughly 6 mm for K-flute), this material is perfect for small packaging, such as luxury items like perfume. F-flute offers even sharper print quality than E-flute.

The corrugated alphabet ends with N-flute. Similar to G-flute, N-flute is made by a different manufacturer. It’s a relatively new type with even finer flutes than F-flute. It provides excellent protection for small, fragile products and is often used for premium packaging or display purposes.

Sometimes a single layer of corrugation isn’t enough — for example, when shipping heavy or fragile products. That’s where double-wall comes in: two layers of fluting separated by an additional liner. This makes the box stronger and more rigid.



Common combinations include:

• B + C flute → the most popular double-wall combination: strong and reliable
• E + B flute → thinner yet sturdy, often used for smaller boxes



For extra-heavy-duty applications, there’s also triple-wall cardboard: three layers of fluting stacked together. This provides maximum strength and is used for industrial or export packaging. A well-known example is A + C + A flute, offering superior protection for very heavy loads.