I spoke with Demco about your air line and they stated that the air line fitting has always been the same. The only difference is that some 2019 and newer Spartan chassis came with a larger fitting installed at the factory, so they made a hose # SM6296 to fit the larger inlet. With your Tiffin being a 2008 (2007 chassis) you wouldn't have the larger fitting so you'll be good to go when installing your Air Force One # SM99243. view full answer...