The materials in the in-wall damping kit are intended to absorb and dampen a significant amount of the acoustic energy radiating from the back of the in-wall speaker's drivers. It is primarily intended to enhance the sonic performance of the speakers. Its ability to reduce adjacent room sound transfer is fairly limited and not its main purpose.
The kit contains the following pieces:
Overall Rating for In-Wall Speaker Foam Damping Kit for LCR 4/7/14/30