For sale is an Aero Precision M4E1 Enhanced Upper with no forward assist. Everything is included; the reciever, barrel nut, barrel nut wrench, and the ejection port door that is already installed. The reciever has never been used or even had anything attached to it. I forgot I had it and I don't plan on using it anymore, so I figured it could go to someone that could use it. Aero Precision doesn't make this model anymore. If you have any questions, feel free to reach out.