Aero Precision M4E1 Threaded .223 Wylde Complete Upper Receiver 18in Fluted Barrel 1-8 Twist A2 Flash Hider ATLAS R-ONE Handguard Black Anodized. 223 Wylde Complete Upper Receiver is a one-piece free float design with built-in anti-rotation tabs....
Aero Precision M4E1 Threaded .223 Wylde Complete Upper Receiver 18in Fluted Barrel 1-8 Twist A2 Flash Hider ATLAS R-ONE Handguard Black Anodized. 223 Wylde Complete Upper Receiver is a one-piece free float design with built-in anti-rotation tabs....