The FAMCO JVO 38 Galvanized Roof Vent - 38 Square Inches Net Free Area. Great for use on pitched roofs, the JVO 38 is one of the best built and most reliable on the market. It features 38 square inches of open space, insect screen, low silhouette and removable hood for access to the attic area when needed. It is open on all four sides for better air flow and unrestricted venting to help elimate moisture and heat built-up. This vent works best when used with soffit or gable end venting. Quality constructed in 28 gauge Galvanized steel. Pre-painted steel color options are: Black, Brown, Gray, and White. The FAMCO JVO 38 Galvanized Roof Vent has a flange measurement of 16 1/2" x 16 1/2". The FAMCO JVO 38 Galvanized Roof Vent is manufactured by Famco in the United States and comes with a 1 Year warranty against product defects and workmanship.