permanent376 ARC upper, MOD 2 with adjustable gas, MLOK, ambi charging handle, all the bells and whistles plus the bullet proof PWS piston system. Upper has roughly 150 rounds in it. Shoots 105gr Hornady black and 106gr Hornady ATip mil match the best(anywhere from .6-.85MOA). Upper is stock minus the Geissele brake I added which includes the install tool if you wish to swap it.
