A heavy-duty 20 gauge steel dipped in enamel (like the white enamel on your stove top) 12' x 8.5'. The enamel is baked onto the steel before inks made with glass get screened onto the face of the white sign. Then the inks are burned into the enamel at 1400 degrees. The end result is a charming, high gloss collectors item that will last for years.