Large sound-absorbing panels weigh more than 4 pounds, high-density pads above 230kg/m3 for noise suppression, attenuation, sound insulation, echo reduction, reverberation diffuser, acoustic treatment, other sound absorption and wall decorationSGS rigorous TEST: with frequency 2000Hz 5000Hz, average absorption coefficient: 0.8, NRC: 0.9 (SGS NO. XMIN190100254CCM), correctly installing enough panels in one space can greatly reduce noise, eliminate sound pollution and improve speech intelligibility, each panel is strict SGS environmental protection test, formaldehyde-free: E0 grade (SGS No. SHAEC1709892601); Fireproof: Grade B1 (SGS No. XMIN190100052CCM) Non-ToxicApplication: Professional Acoustic Control/Treatments, Sound Attenuation, Noise Reduction (Neighborhood Call/Snoring/Piano/Footstep/Talking/TV/Horn Sound, etc.)-Used for ceiling, main wall, TV wall, door, window; Offices, Apartment, Home Theaters, Studios, School, Stage, Rehearsal Rooms, Concert Halls, Podcasting, Churches, Dog CagesEasy Installation: Tiles so light that they can be easily placed on the walls with double-sided (need to buy) tape, without damaging the paintStable physical properties: Our tiles will not expand and contract due to temperature or humidity. Type: Acoustic Sound-Absorbing FoamHome/Cinema - Enjoy your favorite movies with enhanced sound delivered by isolation echoes and reverberation of