Exclude (.html) file type in Web Crawling

(from github.com/MeMeLwin)
Hi,

I was wondering how to exclude certain file types in Web Crawling?
I try the below setting in Excluded URLs For Crawling and it didn’t work .

http://xx.x.xx.xxx/Test/doc/.*.html

What is the setting for excluding (.html) file and where should I put that setting?
In Excluded URLs For Crawling (or) Excluded URLs For Indexing ?

Thank You.

(from github.com/marevol)
Try .*\.html.