The jello-like contents cannot be drunk until it's shaken. Eight shakes and it's a liquidy-jello. Several more shakes, and it's a drink. The can is half the size of a pop can, but opens in the same way. Originally marketed to youth, middle-aged and elderly customers are consuming it for breakfast because it satisfies their appetite and costs only 120 yen—about $1.25.
Source: http://business.nikkeibp.co.jp http://chillcouch.com/?p=204
