There is provided an ink cartridge which is formed from an ink-filled ink pack and a hermetic outer shell case for housing the ink pack and which supplies ink to a recording head by means of application of air pressure to a space between the outer shell case and the ink pack. The wading pool includes a plumbing system for providing the water and a water basin for receiving the water provided by the plumbing system. An elastic rubber section has a minimum inner diameter section, diameter expanding sections, which are disposed at each side in the axial direction of the minimum inner diameter section. At least one second anchor is added within a data portion of at least one data block if the data portion of at least one data block satisfies a predetermined condition. The metal body includes first and second surfaces that do not conform to the compressing surfaces before longitudinal compression of the body and are adapted to contact the compressing surfaces. Thus, electrical connection and data exchange between the two memory cards, either between the first and second memory cards or between the two first memory cards, can be done easily with the contacts of the connection portions.