This heavy barreled Upper Assembly is ready to add your choice of optics or rear sights. The superbly accurate 16" heavy profile barrel is chrome lined and machined from 4150 chrome moly vanadium steel with 1:9" rifling and a right hand twist. It has an A2 flash suppressor and standard A2 front sight. The machined aluminum flat top upper receiver is complete with bolt carrier assembly, forward assist, charging handle and ejection port cover.