Henry 606 80# Premium SBS Modified Mineral-Surfaced Underlayment is a fire-rated cap sheet for quality built-up roofing systems and is formulated for cold weather applications. Additionally, this cap sheet is manufactured on tested fiberglass mat, which is impregnated and coated with a lightly modified rubberized asphalt, filled with fire retardant fillers, and surfaced with mineral/ceramic color coated granules for ultraviolet protection and weatherability.