A very popular alternative to epoxy resins are vinyl ester resins based on bisphenol A, which are moderately reactive. These resins provide high flexibility thanks to high mechanical strength. WILLYBERG resins reinforced with glass fiber/carbon-aramid fiber can be used for the production of machines and electrical parts in contact with water, e.g. wind turbines, elements of large ships. Resins of this type provide high corrosion resistance even at high temperatures. They can be applied by manual, mechanical, cold pressing, pultrusion, casting and RTM methods.