Unique, all-steel gas blocks expand the versatility of your rifle by providing a variety of accessory rail and hand guard mounting options. Especially helpful in customizing short-barreled tactical rifles. Designed Specifically for AR15 's with a barrel .750" O.D. at gas port. Low Profile version is a low and narrow, one-piece block designed to fit inside most free-float hand guards; allows use of rifle length forearms on carbine length barrels for a clean, streamlined look and added gripping surface. Securely attaches to the barrel with included dual hex head set-screws. Works in conjunction with all CMC Triggers AR-15 Nitride Gas Tubes or standard Mil Spec gas tubes and hardware. Features: Machined from 17-4PH Stainless Steel Weight: 0.66 oz Dimensions: 1.35(ht) 1(ln) MADE IN THE USA