Waterproofing underlayment. Composed of a high tack rubberized asphalt coated on a non-woven glass fiber mat. Lower surface has a silicone release paper or film backing. Used at eaves valleys flashings and on low-slope applications to provide watertig. Brand Name: Henry Width: 3 ft. Length: 65 ft. Material: Fiberglass Product Type: Self-Adhesive Shingle Underlayment Color: Blue Coverage Area per Package: 195 sq ft