Flutes are the crinkled waves seen between the walls of any corrugated cardboard. The fluting profile affects both the weight of the box as well as the strength of the walls. Larger fluting also makes the walls of the box thicker, while retaining a light weight.
The first flute developed for corrugated cardboard boxes. Coming in at about 33 flutes per foot, it is the largest grade of fluting. Makes for thick walls.
Originally developed for canned goods that could support themselves without relying on a thick wall structure. At around 47 flutes per foot, B-Fluting allows cardboard walls to be slightly narrower.
The third innovation in corrugated packaging, the C-Flute actually ranks between the A-Flute and the B-flute with approximately 38 flutes per foot. Developed to be a more “all purpose” corrugated box wall. Not as thick as the A, but sturdier than the B.
Slightly thinner corrugated walls, but still sturdy. The biggest advantage of the D-Flute is less bulging at the seams and joints for tighter bulk packaging. Ideal for stacking on a pallet.
The best choice for luxury corrugated packaging. At 90 flutes per foot, the E-flute offers the ideal wall thickness—thin enough to to keep packaging concise, but thick enough for a perceived value. This is the corrugated cardboard seen most at press events and trade shows in the form of marketing kits and display boxes.
The start of the line for “microflutes” in corrugated box design, the F-Flute gives a perceived density with a whopping 125 flutes per foot. Not as strong as the other flute profiles, but certainly lighter and thinner. A beneficial asset for cartons, or other folding corrugated packaging.