You have your ZRODelta Lower, now what? Finish off your next build with a premium, American-made upper receiver from ZRODelta. Our 7075 forged receivers are manufactured to the highest quality standards, right here in North Carolina. Our upper receivers come assembled with dust cover and forward assist. Our Ready Series® upper receivers are best paired with our Ready Series® Complete Ambi Lower, which comes fully assembled with our ELG Fire Control Group, Mission First Minimalist Stock & Grip, and our patented ambidextrous bolt release.