How to restore acoustic foam to its normal size: 1. After opening the vacuum package, place the acoustic foam in a ventilated place for 12-24 hours; 2. Or soak the foam in water for 1 minute, wring it out, then air dry or use a hair dryer. The principle of sound-absorbing foam is that the sound inside the sponge is repeatedly reflected back and forth, which has the effect of noise reduction and sound absorption. Acoustic panels not only have effective sound absorption characteristics, but also do not cause any harm to the body. High-quality studio foam can permanently maintain its sound insulation function. For cleaning, you only need to vacuum and dust occasionally. High-density - flame-retardant material: Sound-absorbing foam plates are made of flame-retardant and environmentally friendly materials, which can be used safely. The absorption spectrum is wide and over 500 HZ. High-density material, which is higher than the industry standard of 30%. At the same time, it can also improve sound quality: by absorbing harmful sounds, reducing fluctuations, reverberation and vibrations, useful sounds are clearer. Installation: It is recommended to attach the tape to the four corners and the middle of the back of the acoustic foam panels and then to the wall. Or you can buy spray adhesive to install sound-absorbing foam according to your needs. For professional acoustic control Acoustic foam Each comes uncompressed and in prime condition With professional acoustic control, sound dampening, acoustic processing, noise reduction, the acoustic foam is to reduce the waves, reverb and flutter in small and medium-sized rooms. Acoustic panels are suitable for sound recording studio, Color: Black Material: Polyurethane Size: 30 x 30 x 2.5 cm Package Contents: 60 x sound-absorbing foam 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 measurement allowed error is +/- 1-3 cm.