Patent ID: 8485378

Claim:
A multi-container package comprising: a lower container comprising: an upper region having an open top; a lower bottom; a lower sidewall; a lower interior space defined by the lower bottom and the lower sidewall, the lower interior space communicating with the opening; an upper container connected to the upper region of the lower container, the upper container comprising: an upper sidewall having a lower region; an upper bottom extending across a lower end of said upper sidewall, the upper bottom comprising: an upwardly protruding valve comprising at least one aperture; an annular channel surrounding the upwardly protruding valve, the annular channel having a downwardly protruding base extending between the lower region of the upper sidewall and the upwardly protruding valve, the annular channel defining a volume located below the at least one aperture; an upper interior space defined by the upper bottom and the upper sidewall, the upper interior space being in fluid communication with the lower interior space and the volume of the channel is a portion of the upper interior space.