WHAT IS CARDBOARD FLUTING?
A GUIDE TO THE WAVY BIT INSIDE BOXES
When you open a cardboard box, have you ever noticed the wavy layer sandwiched between the flat sheets? That wavy stuff is called fluting, and believe it or not, it’s one of the most important parts of the box!
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It's the rippled or corrugated layer you find between the outer layers (called liners) of cardboard. It's designed to make boxes stronger, more durable, and better at protecting what's inside.
WHY IS IT WAVY?
That wave shape (called a “flute”) acts like a shock absorber. It helps:
Cushion the contents inside the box
Add strength so the box doesn’t crush easily
Keep the box lightweight while still being sturdy
DIFFERENT TYPES OF FLUTING
There’s not just one kind of flute! Different wave sizes are used for different jobs:
A-Flute (Thickness ~5 mm)
Excellent cushioning, used in fragile product packaging
B-Flute (Thickness ~3 mm)
Great for printing and folding, often used for retail boxes
C-Flute (Thickness ~4 mm)
The most common, a good all-rounder
E-Flute (Thickness ~1.5 mm)
Thin but strong – ideal for printed packaging and mailing
F-Flute (Thickness ​​​​​​​​​~0.8 mms)
Super thin, used in small retail or cosmetic boxes
Some boxes even combine flutes (like BC-Flute) to get the best of both worlds—strength and flexibility.