Just been outside and found a plastic bit with a rubber end.
Tried to post a pic, but apparently the file size is too big.
So, a more detailed description....
It's approx one inch high and about one inch diameter.
It's round and it looks like there are three small clips on the bottom where it clips into something?
Oh, and it's black!
My car is a Mazda 6, GJ, Tourer.