A similar Kensington cable is available thru apple. It also comes with a wireless remote..
Kensington LiquidAUX for iPhone and iPod - Apple Store (U.S.)

Or a Monster one.. (Very bad reviews tho)
Monster iCarCharger AUX 1000 for iPhone and iPod - Apple Store (U.S.)

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2011 ///X5 M (On Order)

2009 X5 4.8 M Sport Space Gray/Black Fully Loaded

2007 GMC Yukon XL Denali Loaded and Customised