Available in various weights from 4.8kg m up to 13.6kg m, muftilag-R is manufactured using a special ROCKWOOL product which is stitch quilted, preventing delamination and fibre migration and then bonded to a heavy mass layer and finished with aluminium Class O foil facing. Muftilag-R is dimensionally stable under varying conditions of temperature and humidity as well as being compatible with all surfaces on which this product is likely to be used, in normal applications. Guaranteed not to delaminate, or fall apart. Muftilag-R Specifications Average Sound Reduction: 31 dBWeight: 6.8kg m Thickness: 27mmSheet Size: 1200mm x 2m