A: Panels are rated in NRC (Noise Reduction Coefficient) and our bass traps in Sabins (unit of measure of sound absorption during the inch-pound process). All of bass traps and panels are independently examined by Riverbank Acoustics. The upper the absorption # the greater the panel is. Environmental Sustainability: https://beauty-products00987.aboutyoublog.com/39176993/indicators-on-noise-reduction-you-should-know