List readonly files

I need to list or show or query for the files in a folder (well, technically, on a USB drive, but I can navigate to it in Finder/Terminal) that are marked readonly.

All the Google-fu in the world just reveals solutions to change permissions but I don’t need to do that.

My Dashcam marks videos/images readonly to save them when I press the button on it, but they’re still in a folder with a few hundred MOV files, and I need a simple way to filter down to the ones I am looking for.