Product function: used to equip with external m.o.s.t. optical fiber amplifier (audio gateway), when adding aftermarket audio head unit, this module guarantees factory amplifier, speaker and sound quality.Processor function: used to upgrade Mercedes-Benz/Porsche car audio head unit.Compatible with: for Mercedes-Benz head unit replacement interfaceCompatible with: Porsche head unit (PCM2, 2.5) replacement interface)Name:Optical Fiber Audio Decoding BoxWorking voltage:12VApplicable car series:For Benz ML/GL/R class 2005-2012For Benz CLS/E/SLK Class 2009-2012For Porsche Cayenne 2005-2011For Porsche Cayman 997/911 2005-2011For Porsche Boxster 718 2005 - 2011Material: ABScolour: blackPackage Contents:1 x Fiber Decoder Box1 x CableOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.