Applicable to 2004-2010 for BMW (E60): 5 series: 525i, 525it, 528i, 528it, for 530i, 530it, 540i, 540iT and M5 (car and wagon). Allows you to connect an external 3.5mm audio source via a CD changer (eg MD Portable, for MP3 Player,for for iPhoneS,for iPadS,for ,for Laptop. ).
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