The Rise Armament AR-15 Upper Receiver Parts Kit will provide excellent fit and reliable function in your AR-15 rifles and carbines. These parts are great for a new build or replacing worn or broken parts. Kit Includes:Dust CoverDust Cover SpringDust Cover PinDust Cover C-ClipForward AssistForward Assist SpringForward Assist Roll Pin FeaturesMil-spec partsGreat for new builds or replacing worn parts