The FAMCO WVEB Hooded Wall Vent With Screen, Damper, Spring & Gasket. The WVEB Wall Vent is made with a spring loaded damper, gasket and screen. This vent cap is used as an exhaust vent and has a removable screen. Large hood design prevents restricted air flow. Quality crafted of 28 gauge Galvanized steel. The FAMCO WVEB Hooded Wall Vent includes a ΒΌ inch screen to prevent pests from getting in and a built in damper on a light spring for opening and closing.