The dongle is required to flash the sound system with the Volkswagen model-specific sound setups. The SD card in the programming dongle is fully-loaded with most models. The soundbox DSP default setting is Golf, GTI, and Golf R MK7 hatchback models. No programming is necessary for these models. Additional charges: A dealer visit is required to properly code the unit. The programmer is only available via Volkswagen Dealers. Not applicable for DUNE model.