Sound deadening fiberboard is a high-quality, cost-effective solution to airborne sound reduction. SOUNDSTOP favorably increases both sound transmission class (STC) and outside inside transmission class (OITC) values of walls, ceilings, and floors by absorbing airborne sound vibrations. SOUNDSTOP is perfect in applications ranging from walls to ceilings to floors. SOUNDSTOP will exceed your expectations for a quality building product, unmatched in cost-effectiveness and performance.