Sound-absorbing effect is good, FR,Rohs,svhc Noise reduction GB,BS-5852 or TB117 sound-absorbing material absorb a large number of incoming acoustic energy of the acoustic attenuation, reducing the interference and echo sound reflections ,improve the purity of the sound Dear friends, Hello, First of all , thank you very much for your concern of our products,In order to allow faster, more timely for you to provide accurate product and pricing and other information materials,Please send us the inquiry, inform us the following information. Thanks!Providing samples with me is the best approach. Size Demand Quantity Materials and density (weight per cubic meter) Drawings Material Details Useage and product color and packaging requirements sound-absorbing material