The "VAG 908" usually refers to a third-party clone interface designed to function with older versions of the VCDS software (specifically versions around 908.0). It connects a vehicle’s OBD-II port to a computer via USB.
Once installed, the driver allows the VAG 908 interface to perform several professional-grade diagnostic tasks: Advanced Protocol Support: Supports the UDS/ODX/ASAM protocol and for faster module access. Full System Access: vag 908 usb driver 64 bit