A vent window is actually a completely wrong name, especially for fixed windows, and for movable windows, it gives the impression that there is a draft when the window is open, when the opposite is true.
In the 60's, 70's and 80's, it was normal for a car to have small triangular windows that could be opened on hot days without disturbing the passengers. Just open your window and you will immediately get a reaction from your fellow travelers: "It's drafty, can't you close that window". This is not the case with a so-called vent window and the annoying noise is also absent. The hot air is sucked out of the car while driving, which has a cooling effect.
Over the years, the rubbers mounted around the frame become hard and brittle, so that there are very few Volkswagens with original rubber still in new condition.
The rubbers mentioned here are the so-called vertical rubbers against which the window rests when sealing the vent window.
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