... size: 600*600, 600*1200mm thickness: 12/15/18mm acoustic tissue: black felt attached on the back for fireproof and ... ) size: 600*600, 600*1200mm2) thickness: 12/15/18mm3) acoustic tissue: black felt attached on the back for fireproof and ... made on your kindly requestFeature1) Technology products: materials based on acoustic theory, remarkable sound-absorbing function, middle and low frequency sound ...