Owens Corning 703 Acoustic Panels
I have 4 left over OC703 acoustic insulation panels from my DIY project. These are 2' x 4' and 2" thick. You have to purchase them in a case of 6 and I only needed 2 from this last case.
Not worth shipping, but if you are local to the Denver area, I'm selling them for $15 per panel.
My recently upgraded 20 year old basement theater: 7.1 ch setup with JVC x790r projector; 100" Stewart 16x9 screen, Panasonic 820 UHD player; Marantz AV7704 pre-pro; Marantz MM8077 7 ch Amp; PSA v1811 subwoofer; Atlantic Technology 20 year old speakers