Last winter I was redoing my dash and wiring and I cleaned up the defroster outlets, I could only get 2" defrost hose so I cut a piece of big truck inner tube(thick) to wrap around the inlet and glued it with 3M weather strip glue held in place with rubber bands for a day. I wanted to get the hoses in place because it is hard to get to them with every thing in place. Now I find out from this site that you can get 1 3/4" from NAPA,#**#^,. The store is only 1 mile from me.PS I am looking for a fresh air heater for a 1949 chev 1/2 ton.Thanks