Old Question Asked Yet Again

Ok - we are seeing more folks posting odd questions with the context left open. Why, please?

ventilation? forgetfulness?

Ok ok. On Class A and C, some trailers.

Rear windows on what? Their SUV, Truck, Travel trailer, Class A, Class C or Class B?

I haven't noticed people driving with their windows open on anything.

MM.

On trucks? Trailers? Horse drawn carriages? ;)