This vent was designed for a 50mm hole in an enclosure, but should be scalable. It's a work in progress and I've made some changes to make the threads work better, but haven't tested since those changed.

There are versions of the file with the vent cover separated from the vent base. This allows you to print it more easily without supports, or works if you just want to glue the vent cover over your enclosure hole for a permanent solution.