Cupola found on Canadian National Railway (CN) cabooses, and flangers.
Where helpful, windows are recessed on the inside face of the shell to make it easier to install glazing closer to the surface to acheive a closer to flush-glazed appearance.
Note that this cupola is printed in two halves. If this part is being used as part of a greater kitbash project it may be necessary to widen or narrow the overall width of the cupola depending on the caboose body it is being used with. Of course, if you need it regular width, just glue both halves together exactly as they are.
Feel free to get in touch with any questions.