Acoustic Treatment: Bass traps aim to the low/mid frequencies sound wave, Use it together with acoustic foam panels, they will work together to reduce undesirable sound waves, reverb, and flutter echoes. All of bass traps and other acoustic foam products are made from polyurethane, fire-retardant and -friendly. It is safe to use in small-sized rooms. WIDE APPLICATION: It's no double that you will better acoustics and the high end style with cost effective bass traps for studio. Not only great for spot treating sound on walls in your studio also for recording studios, control rooms, rehearsal rooms, /podcast recording, vocal booths, home theaters, home offices. Colour:black Material:Polyurethane Size:about 17.5 x 17.5 x 30cm 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 picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.