N47063 - Nuova Rade Square Topline Vent White 4 inchx4 inch - Louvered vents are molded of corrosion-proof ABS plastic. Will not rust, streak or stain. Predrilled fastener holes. Screw covers included for a professional finish. Use them with Top Line hatches for a uniform look on deck. 3.6 inch x 3.6 inch.