Acousti Tack (ATM) wall panels function as both an excellent tackboard and an effective sound-absorbing panel. These characteristics combine to make our product the choice for tackboards in classrooms, hallways and conference rooms. ATM panels are also lightweight and easy to install. Our ATM panels have a perforated mineral fiberboard core that provides sound absorption by trapping sound vibrations. The mineral fiber core is not wood based; and it will not absorb or release moisture. This ensures that ATM panels will not expand or contract. ATM panels will not warp or shrink after installation.