Low-fuming PermaMop modified roofing asphalt is specially engineered to provide exceptional durability. This makes it a great choice for projects in extreme weather areas, whether it's heat, cold or moisture. In laboratory testing, PermMop asphalt withstands up to 193 weather cycles compared to only 60 weather cycles of other asphalts. That's a minimum of 150% longer than standard asphalt, making PermaMop a great choice for all weather conditions.