Help with Hahcat GUI settings
Hi i am using hashcat gui and everything is working great but have run into a problem.

I am trying to crack a md5 via brute force and i know the following.
It's so many characters long.
It only uses the characters abcdef1234567890

is there something i can do so it only checks those characters.

Any help will be greatly appreciated.
The GUI isn't supported here.
Just a bit of search and you would have the answer :