Attwood Cowl Vents for use with 3 inch ventilation hoses feature a flexible hose flange that is fastened to the hose. The vent is then snapped onto the flange, and the installation is done.

These vents are constructed of chrome-plated die-cast Perma-Plate ZAMAK, and the plastic flange is non-corrosive making these vents ideal for marine environments. They install with standard #8 screws.