cheers for that info guys 
forgive me if i am being dumb, but will you be able to hear the ipod through the car speakers?
?
Yes, the itrip is a low power transmitter that effectively broadcasts the iPod to a spare FM frequency on the cars radio - only has a range of 10-30ft.
So long as you don't turn the iPod's volume up beyond 66% it works very well - you can turn the radio up as much as you like.