I just bought a PTC/Auxiliary heater and plan to retrofit to my 2010 Trail that didnt come with it.
Since i couldnt find the right one, I bought a Prius one on ebay from a 2010 up prius. about 20$. As soon as T4r un-restricts my account (new account), i plan to post a write up.
Lots of vehicles are built to handle this. If the FOB gets wet at the beach or something. Typically they have a removable METAL key for getting in, then you can use the passive transponder chip in the housing to start the vehicle.
I have them on my truck but i am fixing to go all black on the vehicle so they'll go. I think some people call them bullet hole wheels or rotary phone wheels?