Absolute waste of money, poor quality, cheap parts. looks cool though! - Faxon Firearms AR15 Upper Receiver Groups 1

It does not fit properly (Requires hammering the lower pins into the upper in order to fit or filing in contact surfaces). In other words it's out of spec. Noticeable gap between the lower and upper after installation (If you somehow get those pins in the upper). Called their customer service dep and they were not willing to help me with the problem. I have been told that it's just a really tight fit. Don't waste your money on this overpriced upper in my opinion, just buy an Ak instead.