TWIST-ON HOSE FLANGE

For use with 3" I.D. wire-supported ventilation hose. Hose installs from topside by turning the flange into the hose spiral, passing the hose through the deck hole, then mounting ventilator. No hose clamps needed. Corrosion-resistant plastic. Four holes for required #10 fasteners. 3-1/2" diameter installation hole size.