Ideal for coastal locations Everlast siding is virtually... impervious to water. It possesses a thick and solid composite substrate... called C CORE®, made from a blend of minerals and polymer resins, as well as a UV-stable acrylic capstock. The product will never bow, split, swell... rot, or disintegrate, even in the wettest coastal climates. DOWNLOADABLE PDF's Everlast Brochure Why Homeowners Choose Everlast