ROBERTS AirGuard Premium Underlayment is ideal for installation of floating laminate and floating engineered hardwood flooring. It is the only underlayment manufactured with both MICROBAN antimicrobial system plus AirFlow Technology to release trapped moisture, defend against mold and mildew growth, and prevent damage to your floors or subfloors. This premium underlayment features 3 layers of defense: A top layer with an impermeable film keeps moisture away from flooring, a middle layer of thousands of polyshims to help absorb ambient sound, cushion your step and level the finished flooring, and a bottom layer that wicks moisture up from concrete or wood subfloors. Featuring a self-sealing lip and tape system, it's easy to roll out, attach, and cut for fast installation. It covers 100 sq. ft. and measures 40 in. wide x 30 ft. long x 2 mm thick.