Features. Square Aluminum Roof Mounted Vent Weatherwood.. 50 sq. in. Of Net Free Area.. 9 in. Diameter Opening.. As Hot Air Rises The Vent Allows The Hot Air To Escape.. Should Be Installed Up Towards Peak Of Roof For Maximum Exhaust.. Dimension - 3.62 L x 15 W x 16 H in.. Item Weight - 0.38 lbs.