WHAT DOES COLT 6921 FOR SALE MEAN?

Thanks, but when I go the DD MK18 route I feel I am going to devote the additional $20.00 and guidance Intention (but in addition pay out OH tax).   I did check the G&R web page and tried to add the Colt uppers to your cart and get the from inventory message.When you are competing in a contest with your gun, acquiring upgraded Colt AR15 Upper Rece