I am creating a new product that will have 3 large panels of metal. One 6' X 6' , and two 6' X 3' steel sheet panels. I am looking for someone too help me come up with and design a low voltage electric heating option. The hopeful plan is to have the heaters sandwiched between the steel panel and a marine grade sheet of plywood. This product will be living outside so we need to keep that in mind for the design. I want the metal to be maintained at about 50°F (10°C) to keep them free of snow and for defogging purposes. Of course for the heaters, I am looking for the right combination that will be safe, reliable, cost effective, ease of installation, and light weight if possible. Electric anything is not my strong suit, and that includes electric heating. I am out of my league here when it comes to this, which is why I am asking for help with this part of the design.