Introducing the BROWNELL'S EXCLUSIVE ATI Mil-Sport Stripped Upper Receiver: Unleash Precision and Performance Elevate your AR-15 build to the next level with the Brownell's exclusive ATI Mil-Sport Stripped Upper Receiver, the pinnacle of engineering and craftsmanship in the world of firearm components. Designed for discerning shooters and enthusiasts who demand nothing but the best, this upper receiver embodies the essence of precision, reliability, and innovation. Here's why the ATI Mil-Sport Stripped Upper Receiver stands out: Superb Features This USA-made, stripped upper receiver features an ATI forged upper receiver, with a 16"" 1:8 twist, 4150C Mfg: Ati