M16A1 or M16A2?
I sold one of these butts on Ebay as a M16A1 as many here has ID'd these as, but the man who bought it said it was a M16A2. He said it was still a great deal and gave me good FB, but I would like to know for sure what I am selling and don't want to sell something miss identified. Can someone tell me the difference in the A1 and A2?