I have a dark magic that black ring on the opposite side of the screw. what is it called and can you take it out.
It is called an O ring. It is the response of your DM. You can take it out if you work really hard at it with somewhat of a sharp object.
Or a fingernail.
A sewing needle should do the trick, thats how I got mine out.
A safety pin would do well.
I found that some for of a needle works by either prying it out through the side of the oring or poking the oring and prying it out.