Strongwell Thermal Cure Solid Square, Fiberglass and Polyester Resin, Olive Green. Rod is produced using all longitudinal reinforcements with low speed and high temperature, which provides a rich surface appearance. It has no surfacing veil, no pigment and is not fire retardant. On request, Strongwell can quote special formulations including resin type, fire retardant properties, etc. Because it maintains high electrical standards, thermal cure rod is most commonly specified for electrical applications. 20' lengths.