Bri-Rus NSL3013S Smoke 30" x 13" Neo Angle Skylight Cut-out hole&#44; Flange Made of high performance thermoformed polycarbonate to be long lasting and easy to clean. When choosing a skylight&#44; measure your rough hole opening and overall exterior size. Includes care and installation instructions on the box All exterior skylights include a tube of approved urethane sealant that must be used when installing.