Not just your boat hull but your engine lower unit needs protection from the caustic elements of a saltwater environment. For that, Interlux has formulated Trilux Prop & Drive Clear with Biolux Technology, a clear, aerosol antifouling paint for light-colored aluminum outboards and outdrives. Apply the clear spray directly over painted surfaces without primer (bare aluminum should be painted first with a factory finish). Use the spray on any underwater surface where a moderate level of antifouling protection is needed but where paint is not an option. Interlux also makes Prop & Drive in white, gray and black pigments. Retail price for the 12-ounce can is $34.99. Call 800-468-7589 or visit www.yachtpaint.com.