What you see is what you get
I bought this after seeing one a friend had. It is incredibly small and light and pretty much perfect for Adventure Racing. Even though small, the webbing in the leg loops is wide enough to keep things comfortable on rappel, and I expect I could (if necessary) hang in it for pretty long without a problem. The reason a 4 and not a 5 is that it lacks adjustability in the waist. I was too big for the Large, but the XL is looser than I would like in the waist. Since I'm using for AR and not lead climbing, this doesn't pose a significant risk, but I would suggest that if you are buying to climb in and are in between sizes, go down so the fit is snug in the waist.