It's the huma shroud. I get about 60 shots per fill on the reg. After that it starts to fall a bit but it's still usable. The regulator very easy to install just goes in the air tube. It's a sub 12fpe so not a powerful pcp. It's great for the yard. It's by far the most silent gun I have. Squirrels and starlings never hear a thing and at times the Squirrels come out where I have my plinking targets set up. They just go about their business while I do some plinking. Every now and then I do have to knock their numbers down a bit.