Originally Posted by H. Miller
Two sided 3-M tape used by most OEM's for mirrors.
That's what ours are held on with (double-sided adhesive on thin foam). I used tape I had on hand to repair ours when one side came loose, and it has held up well for several years. However, I since found out there is a weatherproof variety available, which is what I would use if I had to do it again. I have seen the weatherproof type in Walmart, but I can't remember what department - automotive maybe?
Caution - if you go to tape, either clean off the silicone really well or put the tape in another area because the tape will probably not stick well to the area where the silicone was.