Interlux Primocon Underwater Primer is an anti-corrosive primer for all underwater metal surfaces. Provides an excellent barrier to reduce pitting caused by galvanic corrosion and an excellent primer for antifouling paint over sanded fiberglass. Primocon can be used as a conversion coating over unknown well-adhered antifouling paint to prevent cracking of new paint. Primocon will not affect the color of antifouling paint.