QT Sound Insulation is a line of high quality sound control underlayments, manufactured in the USA by ECORE International, a leading innovator in recycled products technology. QT is made from 92% recycled rubber and has been tested in over 200 laboratory and field test assemblies. QT has been proven to repeatedly perform as engineered to meet design requirements. The product and engineering support that is provided by QT Sound Insulation guarantees that QT will work as specified, every time.