How to exclude all directories with the name .sync?

I’m just getting started with Duplicati on a Windows PC, and can’t seem to figure this out.

In my source, there are some directories with the name “.sync” (without quotes) that I would like to exclude.

In the GUI, I tried "Exclude folder .sync", but it didn’t work.
I also tried "Exclude directories whose names contain .sync", but that didn’t work either.

Can anyone advise what I am missing here?

(They show up as the following when I edit as list)
-.sync\
-.sync\

Thanks.

–exclude=".sync\\"

Thanks for the reply. I was finally able to figure out the correct config for what I wanted to do:

"Exclude expression *\.sync\" 
or "-*\.sync\" with 'edit as list')