You can blame cpaharley2008 for this. He did a similar mod and I of course did my usual and over engineered my version.
I used 1/4-20 brass furniture threaded inserts for mine. I have plenty of them so why not use them. As a result since they are larger I had to reinforce the mounting area. Luckily I also have an ABS welding kit so I put it to good use.
If you used 10-24 inserts you would not need to do that, they fit with just slight drilling out of the hole. Per Jim's suggestion I installed rubber washers behind the knobs. That helps keep water out and also adds friction to the knobs.
I figure this will help in two ways, one the chance of our vent falling off is reduced and two, since it has holes in it folks will steal someone else's if theirs vanishes.
Have people's refrigerator vents been falling off? It takes considerable effort to get mine to come off even when I'm trying to take it off.
Go on Amazon or one of the other sites where you can read reviews.
Most of the people buying them lost the vent cover and are complaining at having to buy the whole assembly.
We lost one once, but ours went missing at a campground after we had hooked up to utilities. I guess someone needed it more than we did. I see more air conditioner covers than anything but have seen a few refrigerator vents .
I hate to think we're getting to the point we need game cameras located around the trailer while camping to catch thieves ripping off camper parts just to replace items lost or stolen from their camper. Maybe we're already there. Sheesh....
Trailer: Escape#4, 2019 Escape21 DejaView pulled by 2014 Ram Hemi/8sp
I'm not worried about theft, more like losing it under tow. Those plastic tabs break, particularly in the winter when plastic becomes brittle. I have always secured my refer vent from falling off, one way or another, but one can always steal it with merely a screwdriver.
Due to the pandemic, my life now exists of only 3 days, yesterday, today, and tomorrow. Everything else has been forgotten!
I'm not worried about theft, more like losing it under tow.
Oh, I was thinking it was partly to help with the water intrusion issue. Seems like the screws would help keep the sides of the panel tight against the frame and help keep more water out. Hadn't even thought about theft or loss.