The 593 Series is one of the best-selling doors in the Thermacore® line, and offers superior thermal efficiency to fit a broad range of applications. The 593 Series exterior skin is constructed of galvanized steel with a ribbed, textured finish. It is available with a white interior finish and a choice of white, industrial brown, tan or gray exterior. The Thermacore® 593 offers excellent thermal efficiency for medium-duty applications.