Made from 100% polyester fiber, 215kg/m3, better Sound Insulation than soundproofing foam! Sound proofing and flame retardant, odorless, non-toxic, non-slip, corrosion resistant, and anti-aging. Size - 6.83'' X 5.9'' X 0.4'', light weight, multiple colors for decoration. Perfect for individuals to reduce and absorb unwanted echoes, waves, reverb and flutter echoes and wall decoration. Use to spot treat a professional or home recording studio, commercial or home office, rehearsal space, or home theatre. Easy to shape and cut to size, altering won’t affect performance. Both general purpose spray adhesive and double sided tape work. Simply attach spray adhesive or 3M double sided tape (not included) to the back of each panel and adhere in the desired position.