MEKP Catalyst for polyester and vinylester resin and gelcoat systems including our GP Polyester Resin, Clear Polyester resin, ISO Polyester resin. Cobalt accelerator for polyester and vinylester resin and gelcoat systems including our GP Polyester Resin, ISO Polyester resin. MEKP Catalyst & Cobalt accelerator is typically used as a polyester resin catalyst, fibreglass catalyst or vinylester resin systems at a ratio of between 0.5 and 3%, according to the pot-life and cure speed required and the ambient temperature. Always follow the guidelines that accompany your specific resin system.