Flute boxes essentially refer to the reinforcement that makes up the board that runs parallel to the depth of the container to give it its rigidity and crushing strength. As well as providing stacking strength, flutes also provide insulation that protects products from sudden temperature changes.
Flute boxes come in different sizes and varieties to be used for different applications. But generally, the larger the flute the greater the strength and cushioning. And the smaller the flute the better the printability and foldability.