Front sliding window. ~41"x16"

These are all used and taken off campers for various reasons. They all work but might have been hard to open or something like that. Harder to open they we want for a customer. The trim rings will have already been screwed on at some point so you'll want to make new screw holes in the trim ring.  Designed for 1" wall thickness though with longer screws you could make it fit thicker walls.