[SELF-ADHESIVE,NO TOOLS REQUIRED, Easy to Install]No extra money is needed to buy glue,the back of each board is already covered with glue, you just need to tear the paper and . ( make to press each place on the block to make the sticking more .) Achieve the sound absorption and reflection soundproof wall panels, achieving maximum surface area for the utmost sound control. Easy to shape and cut to size, customizing the shape you like and 't affect performance. odorless, non-toxic,formaldehyde-free and have thousands of pores inside, which makes breathable and moisture-proof. While keeping the room dry and safe to in and touch. Perfect for individuals to reduce and unwanted echoes, waves, reverb, and flutter echoes. Reduce echoes and increase musical . Perfect to use learning room, gaming room, recording studio, theaters, concert and more. color: grey Material: Polyurethane Package Contents: 12 x Acoustic foam Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.