Aero uppers - Aero Precision M4E1 Threaded 10in .300 Blackout Complete Upper Receiver with Flash Hider

Quite simply one of the best uppers you can find for the cost you pay. I’ve used many other companies and you can spend over $1000 for similar products. I’ll never spend that kind of money again because Aero is the right product for the right price. I find that most of the bad product reviews are written by people who truly don’t know how to put things together.