Dension Gateway 500 Extension Kit EXT1GW5 Extension kit is used with Dension Gateway 500 for its successful installation into various Porsche vehicles: Porsche Cayman, Boxter and 911 equipped with a CD Changer. If the Porsche vehicle is equipped with a factory CD Changer, the GATEWAY 500 interface shall be installed at the factory CD Changer location. For this type of installation an extension kit for the USB, iPod and AUX cables is required to route the wires inside the vehicle.