Attwood Twist-On Hose Flanges are designed for 3 inch wire-supported ventilation hose. Resistent to gasoline, moisture, and rot, these flanges eliminate the need for hose clamps. Hose installs from the topside by turning the flange into the hose spiral, passing the hose through the hole in the deck, then mounting a ventilator.
Flange installation hole diameter is 3.5 inches, and each comes pre-drilled with three mounting holes that can accommodate #10 screws. Black polyethylene construction withstands harsh marine environments and resists cracking.