The stuff I used to connect my iPod :
Belkin Auto Kit for iPod w/ Dock Connector
The Auto Kit charges your iPod from your car's cigarette lighter and and provides an adjustable amplifier and 3.5mm audio-out jack.
Belkin TuneDok Car Holder for iPod
The Belkin TuneDok makes it easy to take along your iPod and play tunes in your car. TuneDok provides a very good stability, along with flexible construction for a perfect fit in your 1-Series's cup-holder console.
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