A circuit board of an ink cartridge is provided with a plurality of terminals, with the contact portions of the plurality of terminals forming a plurality of lines. The contact portions of two terminals used for detecting installation are positioned in a first line, and the contact portion of a power terminal is positioned between the two terminals. The first line may be positioned to a leading side when the ink cartridge is moved in a prescribed direction to effect installation in a printer. Alternatively, the first line may be the line closest to an opening of an ink delivery port. Alternatively, the first line may be the line closest to an ink delivery needle.