We often need to protect steel from the elements and from temperature swings. Elastomeric coatings fit the bill quite nicely. The best brands, such as FX-501M from Fox Industries, are made from 100 percent acrylic polymer, which is a long chain of acrylate or methacrylate molecules. The polymer is waterbased and forms a tough, corrosion-protective film on metal. Other ingredients are added, such as diphenyl ketone (a UV-ray protectant) ethylene glycol (an anti-corrosive), and coloring agents.