Yacht Chandlers has a large range of Marine Paint Primers and Undercoats from a range of suppliers such as International, Hempel and Bonde Marine. Marine Primers are to be used on underwater surfaces which include steel, aluminum, wooden and GRP hulls. Underwater Primers provide a barrier to reduce pitting of metal from galvanic corrosion. Use as a primer for antifouling paint over sanded fiberglass, wood or over an unknown antifouling paint. Other undercoats are for the use one part and two part topcoats.