What pen or pencil is he using?

Hello I am completely new to sketching and drawing and really missed out the first 39 years of my life. But since my kids asked me to draw together I figured out it gives me so much peace of mind.

So I was checking videos out on YouTube and was wondering what pen or pencil Dan Beardshaw is using for this marvelous piece. It looks like a fineliner but the lines look like a pencil. Anyway it looks really comfortable. (Not that I can ever reach this skill level)