Flutes come in several standard shapes or flute profiles (A, B, C, E, F, etc.). Corrugated Flutes are the S shaped waves/arches of a corrugated box that makes up the board. This is called the boards corrugation. Flutes are essentially the reinforcement that make up the board. They run parallel to the depth of the container and give it its rigidity and crushing/stacking strength. As well as providing stacking strength, flutes also provide insulation that protects products from sudden temperature changes. Generally speaking, larger flutes like A & B profile provide greater strength and cushioning, while smaller flute profiles like D & E provide better printability and foldability.