Ever since introduced the six-can pack for beverages in 1994, about 10% weight of cardboard has been reduced. Providing a holding structure at the bottom can improve the holding strength about 1.5 times and ensuring safety during transportation and handling, the weight of the cardboard was reduced by 14%, and its area was reduced by about 15%. Furthermore, convenience is improved by perforations which enable tearing open from both the right and left sides, regardless of handedness, and the required opening strength was reduced by about 30%.