Orgill 15RF Roofing Felt, 144 ft L, 3 ft W, Pack of 30Saturated utility felt is a uniform, flexible felt of organic fibers, impregnated with an asphalt saturant. Used as an underlay beneath asphalt shingles, wood shakes, tiles and other sloped coverings. Meets ASTM 4869 Type I standard. 30RF has twice the thickness of 15RF. Approximately 36 lb per roll. Unit: ROLL UPC: 717975104328 Model Number: 15RF