| E | Flute height mm1.1 to 1.6 | Flutes per 300 mmabout 90 | Board thickness mm1.5 to 2 | BehaviourThin profile, fine print face | Typical useMailers, retail cartons, inserts |
| B | Flute height mm2.2 to 3.0 | Flutes per 300 mmabout 50 | Board thickness mm3 to 3.5 | BehaviourRigid flat crush, good print | Typical useDie-cut trays, FMCG cartons |
| C | Flute height mm3.5 to 4.0 | Flutes per 300 mmabout 40 | Board thickness mm4 to 4.5 | BehaviourBalanced stacking and cushioning | Typical useGeneral shipping RSC |
| A | Flute height mm4.5 to 4.8 | Flutes per 300 mmabout 33 | Board thickness mm5 to 5.5 | BehaviourMost cushioning, lower flat crush | Typical useFragile and light-stack goods |
| EB | Flute height mmE over B | Flutes per 300 mm90 over 50 | Board thickness mm4 to 5 | BehaviourFine print face, rigid B core | Typical usePrinted retail-ready shippers, FMCG |
| EC | Flute height mmE over C | Flutes per 300 mm90 over 40 | Board thickness mm5 to 6 | BehaviourFine print face, C for stacking | Typical usePrinted shippers for stacked goods |
| EA | Flute height mmE over A | Flutes per 300 mm90 over 33 | Board thickness mm6 to 7 | BehaviourFine print face, most cushioning | Typical useFragile goods in a printed shipper |
| BC | Flute height mmB over C | Flutes per 300 mm50 over 40 | Board thickness mm7 to 8 | BehaviourStacking and puncture resistance | Typical useHeavy industrial and export packs |
| BA | Flute height mmB over A | Flutes per 300 mm50 over 33 | Board thickness mm8 to 9 | BehaviourRigid face, cushioning core | Typical useHeavy goods that need cushioning |
| CA | Flute height mmC over A | Flutes per 300 mm40 over 33 | Board thickness mm9 to 10 | BehaviourThickest build, stacking with cushioning | Typical useExport and long-haul freight, machinery and spare parts |