What type of glue for behind windscreen
 

I've got an A pillar pod, that every summer falls off due to the glue I have used to stick it too the pillar. It's obviously getting heated up by the sun and weakening the bond.

Any idea's what glue to use to prevent this? Possibly the same stuff they use on windscreens themselves, what's that?

Windscreen adhesive would be total overkill for this situation, as you'd have to buy a screen sized tube of it, and they usually need a special powered applicator/mixer gun. If you need something thermally stable and broadly the right colour, a good silicone based black bathroom sealant would probably be just the ticket.

wurth bond and seal we use in work for stuff like that.

any sort of quick dry epoxy resin will also do the job... B&Q stock a few good ones for a few quid.

HTH
Regards
David