An accessory device comprising an accessory device housing having a surface that is adapted to be adjacent a computer housing when the accessory device and computer housings are attached together. The accessory device also comprises an electrical connector provided on the surface of the accessory device housing. The electrical connector is adapted to receive an electrical mating connector from the computer housing. A recess is formed on the surface of the accessory device housing that corresponds to an air vent in the computer housing when said computer housing is attached to the accessory device, thereby enabling air to flow through the recess and air event.