Audi A3 A4 A6 TT Models Car Stereo Steering Wheel & BOSE Amplified Conmined Retention Interface Kit. T1 Audio latest SWC with MPB & BOSE Amplifed Interface. Not only does this kit do this feature but if your vehicle is fitted with a factory BOSE system which could be rear or fully amplified it will by pass the amplifier allowing you to carry on using the existing factory sound system with your new stereo.
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