An ink cartridge includes a first wall, a second wall opposite the first wall, and an ink supply portion positioned at the first wall. The ink cartridge also includes at least one third wall which is substantially perpendicular to each of the first wall and the second wall, a fourth wall which is substantially perpendicular to each of the first wall, the second wall, and the at least one third wall, and a fifth wall opposite the fourth wall. The at least one third wall has a first recess formed therein which is adjacent to and intersects the fourth wall, and the first recess extends from the first wall towards the second wall. Moreover, the at least one third wall has a second recess formed therein which is adjacent to and intersects the fifth wall, and the second recess extends from the first wall towards the second wall. In addition, the fifth wall has a concavity formed therein, and the concavity intersects a portion of the second recess.