Sea Dog Stainless Steel Clam Shell Vent Large Escudo De Armas De Portugal Ilustracin del Vector Ilustracin de. Stainless Steel Clam Shell Vent Large Large Clam Shell Ventilators provide splash protection for vent holes, wires, cable runs, or blower exhaust hose openings. Corrosion resistant 304 stamped stainless steel construction. Can be used for cabin ventilation with the addition of a dorade box. Clam Shell Vents are ideal for applications where a taller vent would foul lines or restrict crew movement. Easy to install with pre drilled holes for five #6 RH fasteners (not included). WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings. ca. gov.