Machined from billet 7075-T6 aluminum with a mil-spec hardcoat anodized finish, LANTACs UAR Upper Advanced Receiver for the AR-15 delivers reduced friction and ultrasmooth operation. The super-smooth burnished bore minimizes bolt-carrier friction, while the concentric barrel nut threads and bore- and barrel-extension surfaces remain perfectly perpendicular to the barrel and fixing assembly. An integrated blended Smoothcam system with domed head, low-friction cam pin and upper receiver operate with minimal wear and tear. Cam pin is machined from stainless steel, polished and finished with copper/brass. Plus, it operates with the head curving away from the receivers internal surface, preventing wear. M4 feedramps are standard. Package includes a CP-R360 domed-head cam pin. Made in USA. Wt: 8.8 oz. Color: Stainless Steel. Type: AR-15 Uppers.