Inside Corner – Coated with Galvalume, a patented aluminum-zink alloy coating for extra protection. Panels are then bonderized and an OPTIMA Primer is applied. The primer supplies flexibility and provides an excellent base for the final coat; CERM-A-STAR. This ceramic pigmented silicone polyester not only supplies strength, but also hardness and durability against the effects of sun, wind, rain, heat and cold. It is extremely resistant to mildew. This also keeps the panel from blistering, peeling or flaking.