Complete E3 mod2 upper, with knights castle nut proprietary gas block, straight gas tube and their intermdiate(?) length gas system (longer than mid/shorter than rifle). Shoots very soft.
FCD/rearden collab a2 style flash hider/suppressor mount that has been autistically leveled, torqued, shimmed, rockset properly.
Everything is factory knights less the flash hider and Magpul covers.