Patent ID: 8164907

Claim:
A system, comprising: a communications device comprising a volume and an outer surface; a first power supply unit detachably installable to the communications device; a second power supply unit detachably installable to the communications device; and a third power supply unit detachably installable to the communications device, wherein the communications device has on the outer surface an aperture configured to enable insertion of the first power supply unit into a first section of the volume inside the communications device, said first power supply unit including electrical connectors configured to connect with first electrical connectors of said communications device when said first power supply unit is inserted in the first section of said volume, and wherein said aperture is also configured to enable insertion of the second power supply unit into a second section of said volume, said second power supply unit including electrical connectors configured to connect with second electrical connectors of said communications device when said second power supply unit is inserted in the second section of said volume, and said volume being continuous such that, in place of said first and second power supply units, the third power supply unit can be inserted through said aperture into said volume, the third power supply unit, when installed, extending into both said first section and said second section of said volume, and the first electrical connectors of said communications device configured to provide electrical connections with electrical connectors of the third power supply unit.