That way it’s easier to tell if there is an rv propane leak It is easy to install and can last up to 60 months. Because propane gas is heavier than air, rv manufacturers install a propane detector close to the floor of the rv, to hopefully sound the alarm if there is a propane leak so you can evacuate (and turn the propane valve off).
Zkmiles R501 RV Propane Gas Detector for Motor Home, Travel Trailer
This rv gas leak detector can tell if there is a dangerous concentration of propane or natural gas in the rv