Going backwards

The car we have has the ability for ipod connectivity and having had the car for nearly three years and after finding out it would not accept my dearest's fifth generation ipod an oppertunity arose to get a slightly older model from a Police Lost and found auction.

My dearest duly returned from the auction with the required ipod in very good order and working perfectly which was not bad for eight quid all in but we are not sure what generation it is.

Any suggestions or confirmation would be much appreciated.

Down side was that this was not all my dearest came home with so now counting the cost but it is amazing what these auctions turn up bargain wise.