VW Sharan Stubby aerial About £9 on eBay.
They look great and there is no loss of reception.
Does it sit flush with the base?
Great question Kevin.
Well I must admit, when I screwed it in to the base, it was a little long and didn't screw all the way down.
All I had to do was cut 2/3 threads off the screw with a junior hacksaw. Took about 30 secs.
Then, yes it does sit flush.
I will try and find a better picture.