hat
Plan: akòz koton son absorption dégradé èstrikti unique, li rezoud an komen polyestè optique D' son koton kapab sèlman elimine limit segondè frekans tande, pale, ets
eng
Purpose: due to the uniqueness of gradient structure sound-absorbing cotton, it solved the common polyester fiber sound insulation cotton can only eliminate the limitations of high frequency sound, voice, etc