The M5SD Shroud has a free-floating design that won't scar or damage your barrel. The overall length is 14 inches that adds a total of 10 inches to your gun. The outer diameter is 2 inches at base, 1 inch at the nose and an inner diameter of 1 inch around the barrel. The construction consists of a glass-filled nylon composite and is easy to install by bolting to the gun body (long bolts provided).