The 418 Series is a high-quality, heavy-duty insulated door that provides protection against heat and cold environments.  Fabricated of 16-gauge, flush galvanized steel exterior and 26-gauge steel backcover, these 2" (51mm) thick doors offer the choice of expanded polystyrene or isocyanurate insulation for R-value´s up to 11.69 (2.06 W/Msq).  A wide array of options allows these doors to meet the most stringent project requirements that call for a degree of thermal efficiency.