The 422 Series door is ideal for heavy-duty applications requiring protection against the elements.  These doors feature a 2" (51mm) panel thickness, 16-gauge steel intermediate and end stiles, ribbed steel exterior and 26-gauge steel back cover in a white finish.  Polystyrene insulation (R-value of 7.35 or 1.29 W / Msq) is standard, and isocyanurate insulation, with an R-value of 11.69 (2.06 W / Msq) is an option.  The 422 Series is a 20-gauge steel door available in sizes up to 29´2" in width and 24´1" in height (8890mm and 7341mm).  A multitude of options -- including reinforcing struts, movable center posts, and motor operation -- allow these insulated heavy-duty doors to be used in a variety of commercial and industrial environments.