I have just removed this from our Zafira because we have ordered a new head unit that has an ipod connector integrated. I have 2 of these as one was going into the Lexus.
Its a standard unit that requires power (from your 12V radio supply) and a din input, It plugs into your aerial socket of your head unit and the roof aerial plugs into this. Hides behind the dash so its not on display.
You just tune your FM to 88.3 or 88.7 (selectable) and away you go. Its better than the Itrip because its hard wired and does not cause interferance or get all stroppy when another itrip is close by.
Im lookign for £15 inc P&P for it.
Pic is an almost identical one from ebay.
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