Chem-Bake® One Step is a 2 component hi-solids acrylic polyurethane finish that has superior color and gloss retention. Chem-Bake® One Step is designed as a self-priming system for repainting prefinished metal surfaces including SMP coil coated sheet metal used in rolling steel doors, roofs, gutters, and metal siding. It can also be used as a DTM (direct to metal) finish on steel. High-Gloss finish. Requires activator.