Designed for underslab use to prevent moisture migration, Viper VaporCheck II acts as a barrier and retarder. The multilayer, plastic extrusion product is manufactured from prime virgin polyolefin resins and provides low water vapor permeance, high-tensile strength, and the ability to resist punctures and tears during rigorous installation. Available in gray 10-mil 14x210-ft. rolls and blue 15-mil 14x140-ft. rolls, both options are Class A vapor barriers/retarders under the ASTM E 1745 standard. A 10-mil, Class C option also is available in a 14x210-ft. roll. Insulation Solutions Inc. 866-698-6562.