Soucy Composites uses a large assortment of thermoset resins. Polyester resins are the most widely used resin systems. Vinyl Ester is similar, but offers better chemical and mechanical properties. Epoxy represents some of the highest performance resins, which leads to their almost exclusive use in aircraft and recreational components. In addition to polyesters and epoxies, Soucy Composites uses a number of other specialized resin systems, such as vinyl ester, phenolic, urethane and silicone.