In part, and in addition to apparatus and methods presented, an expansion board to be connected/disconnected to/from its mother board easily is provided. A face of a CDC (Communication Daughter Card), which is an expansion board to be connected to the mother board of a computer system is covered by an insulating sheet. In the CDC, an edge of one end of this insulating sheet is extended so as to form a projection. A user can take this projection with fingers, thereby carrying and connecting/disconnecting the CDC to/from the mother board easily.