I saw another post about that same vent recently, not sure if it was here or another forum. Think it was here. Anyway, they said they bought it from Forest River. Is it an Onan part or something that Forest River sources?
I can attest that just a vent through the door, without the duct/boot, doesn't do a lot of good. I found a nice looking louver at West Marine. Think I made a post about here back in the summer. The upshot with mine is the louver looks good and was cheap. It's square and a bit smaller than that Forest River one, but I feel like it's big enough. It just doesn't pull a lot of air through it since it's getting almost all it needs from around and under.
I plan on jurry-rigging something using a door sweep weather strip at some point, to simulate that duct that comes with that purpose made vent.
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