Start your new build with a Luth-AR .223/5.56 A3 Flattop Upper Receiver comes fully assembled with an M4-type feed ramp, 12 position Picatinny accessory rail for mounting scopes or flip-up sights. Shell deflector, forward assist, and ejection port cover. Precision machined from a 7075-T6 aluminum forging and hardcoat anodized for a tough, scratch-resistant coating.