I bought one as part of a security kit on special at Jackson Center when I was there in November. The kit had a propane detector that is to be hard-wired into the
12V system of the coach.
The smoke detector in the kit was the normal type, operating on a 9V battery, but perhaps the LP gas ones requires too much current to do that.
Maybe call them, get to the switchboard and ask her if they still have them. The receptionist seems to run the "Wally Byam" store they have.
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“Courage is being scared to death, but saddling up anyway.”
...John Wayne...........................