Originally Posted by
PatrioticDisorder
Check out the URX4 install video, too complicated for me. Part of the reason the Mod2 gas tube & gas block were completely changed I think is to make life easier if you ever want/need to remove the URX4 rail... Another thing is KAC is not selling Mod2 uppers, I don't believe anymore mod 1 uppers are being made so you may be need to be very patient in waiting for thr mod2 uppers to leave the factory, I doubt we'll see the uppers anytime this year. As great as KAC stuff is out of the box, IMO it's not really worth that kind of wait.