This nifty little plastic vent cover was a factory option on your Westy. It is designed to slip over the stainless flue vent and keep rain, soapy water and pesky bugs from getting in making a mess of things. While it is possible to drive with the vent cover in place, we suggest that you only use it while the vehicle is parked, in storage, or being washed. If you drive with it on, you risk losing it!
These can be a bit tricky to install at times. If you are experiencing difficulty installing this part, we suggest either:
1) heating it up a bit with a hair dryer (to increase malleability)
2) cutting a small slit in the edge to improve fitment.