Clam shell ventilators provide splash protection for vent holes, wire or cable runs and blower-exhaust hose openings. 304 stamped stainless steel construction. Can be used for cabin ventilation with dorade boxes. Great for locker vents. Clam shell vents are ideal for applications where a taller vent would foul lines or restrict crew movement. Pre-drilled holes for a smooth screw on installation. #6 RH fasteners not included.