The sound absorbing foam is made of flame-retardant and environmentally friendly materials, which can be used safely. Wall low-frequency sound-absorbing cotton, which effectively improves sound clarity, sound absorption and noise reduction; Eliminate the first reflected sound, reduce the reverberation time, and reduce the between the side walls; After opening the Vacuum package, soak them in water for 1-3 minutes, wring it dry gently, and then place it in a ventilated place to air dry or use a blower to dry. 2. Place the soundproof panels in a ventilated place for 24-72 hours. Suitable for professional studio, recording studio, voice studio, control room, rehearsal room, concert hall, podcast, etc., also can be used for church, home theater, professional theater, home studio, office, utility closet, etc.Can handle walls, ceilings, doors, etc. Colour:black Material:Polyurethane Size:12 x 12 x 24cm Package Contents: 12 * absorbing foams Only the above package content, other products are not included. Note: Light 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.