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).