High-Density Flame-Retardant Material: These sound-absorbing foam panels are made from flame-retardant and eco-friendly materials, ensuring safe use. The absorption spectrum is broad, exceeding 500 HZ. The high-density material surpasses the industry standard by over 30%. Improve Sound Quality: By absorbing harmful sounds, reducing fluctuations, reverberation, and vibrations, these panels clarify useful sounds. The principle behind the sound-isolating foam is that sound repeatedly reflects within the sponge, achieving noise reduction and sound absorption. These acoustic panels not only offer effective sound absorption but also pose no harm to the body. The high-quality material of the studio foam permanently maintains its sound insulation function. For cleaning, simply vacuum or dust occasionally. How to restore the acoustic foam to its normal size: 1. After opening the vacuum packaging, place the acoustic foam in a ventilated area for 12-24 hours; 2. Alternatively, soak the foam in water for 1 minute, wring it out, and air dry or use a fan to dry it. Installation: It is recommended to attach tape to the four corners and the center of the back of the acoustic foam panels and then to the wall. Or, you can purchase adhesive to install the sound-insulating foam according to your needs. For Professional Acoustic Control: Each acoustic foam panel arrives uncompressed and in perfect condition! Offering professional acoustic control, sound dampening, and acoustic processing. Size: 30x30x2.5cm Material: Polyurethane Color: Black+red Package Contents: 24 * Black sound-absorbing cotton 24 * Red sound-absorbing cotton 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 to be slightly different from the real thing. The allowable measurement error is +/- 1-3 cm.