Custom 416 made from a bone yard one I received from a friend a year ago almost every part of the gun was replaced upper in broken so it held together with tape at the end but other then that is a sturdy build. Not missing screw for but stock and charging handle is not attached to upper. Parts I know of include Shs 18:1 gears Angel customs tight bore G&G stock hop up and bucking Kwa high torque motor M95 spring Can come with attachments For extra