Ever lost or mislaid the cover from the fill point? left it at a petrol station? had it nicked by some scroat with nothing better to do? yes I know most of them have a dangle cord, but they do break, the answer is here, please see the item in the gasure.co.uk website in the product section under adaptors, comes complete with 2 keys, the key cannot be removed until the cap is on the vehicle, nice idea.
ps Sven yours is on its way, did you get the little darling that nicked it?