Trimline VariaVent Ridge Vent combines ridge ventilation and variable weather blocking in one product. Each vent comes in a 4-foot sections with aluminum weather blocking already attached. The variability of the weather blocking will allow the vent to fit any tile and metal on the market, while forming a weather-tight seal, meeting the Tile Roof Institute's requirements for weather blocking and ventilation. VariaVent allows venting at the hottest point, the ridge line. This eliminates attic hot spots, reducing cooling costs by removing hot moist air from the attic, prolonging the life of the roof.