Auralex 4PYR24FGR 4 Studiofoam Pyramid Panels in Forest Green 6-2'x4'x4 panels Pyramid cut offers superior sound absorption and an aesthetic look Effectively reduce standing waves and flutter echoes as well as provides low frequency absorption Won't crumble with age Absorbs up to 60% better than other brands with an NRC of .95 Class B Fire Rated