Just the soft flexible lip and a foam ring to seal it, judging from the dust , not good enough.
I cleaned the area with wax and grease remover then scuffed the area with a scotch pad and cleaned again.
Then a ring of ATV silicone around each hole and just inside the lip of the antenna and reassembled. Not too happy with the nut/tension bolt on the inside, I could not get it to pull down to my liking but it was going to strip if I put too much tension on it.
Ill give it 24 hrs.' to set up then put the hose to it and see.