For use with Ondura Premium Series 10 Asphalt Roof panels, the Ondura Premium foam closure strips seal the open space created by the corrugations of the roofing panels. Use the vented closure strips at the eave and ridge to allow airflow beneath the corrugations and to help keep out rain, debris, and insects. Installation Tip: Place closure strips under the Ondura panel with the curved side up to fill the corrugations. The closure strips must be placed where the fasteners will be located so that the fasteners will securely hold the closure strips in place. Pack QTY of 4 individual premium vented closure strips. Each closure strip is 42" in length. Approximately 14 linear feet of coverage per pack. Easy to cut and install.