... 9mm,12mm,15mm or 18mm.It is also acceptable to use the other board according to the customers' requirement.2. ... according to acoustic theory,excellent at reducing noises,especially effective for absorbing high and middle frequency noises.2. Artistic products : ... machine room,researching lab,factory shop,gym,school etc.all these are in need of sound absorption materila. Wooden Acoustic Panels for home ...