StormStop ridge vent provides superior protection that stops snow, rain, sand and bugs from entering the attic. Fitted with our patented weather-blocker, this spun-bound material is 71% open and 29% closed. This technology allows the materials exterior surface to repel water so that it beads up and rolls out of vent, while the interior surface remains breathable to allow air and moisture to flow out. Designed without an external baffle keeps ridge vent clog-free from pine straw and leaves. Durable and impact resistant, ridge vent is made of HDPE plastic to withstand hail damage and gun-nailable for fast and easy installation. Delivers the best protection and ventilation along with the most sleek design for a clean, neat and long-lasting roof appearance.