ALEXSEAL® Finish Primer 442 is an epoxy-based finish primer offering advanced adhesion qualities over various substrates, exceptional sanding characteristics, and good film build. The product's special characteristics ensure a reduction of cleaning and maintenance, while at the same time preserving the yacht's appearance and value. Designed to prime and seal old and new, properly prepared, stable surfaces such as gelcoat and fiberglass, as well as to seal other ALEXSEAL® primers and filler systems. Using this primer as a base enhances the 'Wet Look' of ALEXSEAL®'s Topcoats. May be used above and below the waterline.