I was able to easily install on my travel trailer which has a Truma combination water heater and furnace. Though it talks about 110mm outlets it really does not tell how big it is in diameter. It is about 127mm in diameter, so it is a little bigger than you might expect. For the premium price paid I would have liked some sort of soft edge material between the screen's metal edge and my fiberglass trailer exterior. I ended up slitting a small, approximately 1/8, rubber windshield washer hose and installing it around the edge of the screen. Good fit and it protects the side of the trailer. The rounded ends of the springs were a little hard to attach to the screen so I bent them slightly to make them easier to get though the screen grids. Seems to have plenty of pressure to hold everything in place. Otherwise this was a good quality screen, though a little expensive, that should last for years.

Yes this fits the Truma vent perfectly but the installation springs are useless because the Truma isn’t a typical vent. If I had known it was only the size that was custom to this vent I would have gotten a cheaper screen. I ended up using some wire to attach so it does work, just paid more than I needed to

This screen is larger than the Truma Vent on our Class B van - Due to the shape of the Ford Transit sides you will have to add something to fill in the gap between the vent and the van. too large.

It is nearly impossible to install. Really a very poor design and the little wire installation tool is a useless piece of garbage. Overall this was a waste of money.