For sale is an Aero M4E1 upper with an 11.5in barrel. Does *not* include a bcg or charging handle, but comes with a primary arms GLX 2x prism and magpul back up sights. The flash hider will have to be installed. There's less than 100 round through the barrel, asking $500 and must meet in Killeen. If interested, text 254-616-0475.