This 30-inch retractable downdraft vent rises 13.5 inches to help filter steam from tall stockpots, and remains flush with the cooking surface when not in use. The 585 CFM Motor Class* ventilation system has the power to provide effective venting for most cooktops or ranges. The system is reversible to help fit in the cabinet space under the vent. Performance varies based on installation. Resources available at AHAM.org