Magpul is the best - Hogue AR-15/M-16 Overmolded Collapsible Buttstock

These stocks are great, one thing to remember when ordering is there are two sizes, Mil spec 1.15 and Commercial 1.17, you can use commercial on mil spec but not the other way. The enclosed stock adjustment lever is a plus if you’re shooting from a rest or bi-pod, I found out the hard way that when you brace the backend with an exposed lever there is a good chance you’ll dot your eye on an AR10.