CertainTeed's Shadow Ridge Algae Resistant a premium ridge cap shingle designed to provide excellent protection and an attractive finish for residential roofs. This specialized roofing accessory is made with high-quality materials and features a unique design that provides exceptional wind resistance and durability. Shadow Ridge is a ridge cap shingle that is designed to fit over the peak of a residential roof. It is made with durable asphalt and granules, which give it a weather-resistant surface that can withstand the elements. The shingle is also designed to be compatible with most types of asphalt shingles, allowing for easy installation and a seamless appearance on the roof.