All of the parts are plastic including the flimsy 1/8" plastic pivot pins built into each end of the flap.
One of the plastic pins broke after using it just a few times. When I went to the dealer for a replacement, I was given two choices.
It seems to me that the typical noisy fan is just part of the issue with using the vent.
Either the plastic pivot pin model or a model where tape was used instead of pivot pins and sockets.
Unbelievable cheap ****! I ended up rebuilding the pivot model using a pieces of coat hanger for the pivot pins.
I guess my rebuilt works great, but I hardly ever use the vent.
The next issue is the locking tabs.
My model has two plastic tabs, on the outside of the camper, that must be put in place to hold the flap when driving.
Not only is it inconvenient to go outside to lock or unlock the flap, but the tabs are too high off the ground to do so without a step stool or small ladder.
Instead of using the vent, I have just crack the nearest window and use fantastic fan to pull air through the camper.
That works poorly and also puts greasy residue on the fan blades but at least I don't have to hear the noise of the vent fan after first going outside with a step stool to unlock the vent.