What is this second grey bar on my UI?

Anyone know what this second bar on the bottom is?

I know the first one is from Quartz as a swing timer (well, bow timer as I am hunter) but I have no clue what this second bar is and it kind of annoys me.

https://gyazo.com/b22a7545ead1df3ccde292bfb89e22cb

I don't know how to delete my post but if anyone else is having this issue, it is the GCD timer