Geissele Automatics Super Duty MOD1, Complete Upper Receiver, 5.56 NATO, 16" Barrel, 1:7 Twist, HUXWRX Flash Hider-QD 556, 15" SMR MK16 M-LOK Free Float Handguard, Geissele Airborne Charging Handle, Nanoweapon Reliability Enhanced Bolt Carrier Group, Fits AR-15, Anodized Finish, Black 08-548B