CRUX SOCVW-21CRUX (SOCVW 21) RADIO REPLACEMENT INTERFACE FOR VOLKSWAGEN VEHICLES The CRUX SOCVW 21 is a radio replacement interface for select Volkswagen vehicles. It facilitates the integration of an after market radio to retain factory features with Amplified and Non Amplified Systems. FEATURES: Retains factory features in select Volkswagen vehicles 2002 up Retains factory installed amplifiers With navigation outputs (Reverse gear, Illumination and Speed signal)