Sectional Steel Door model 422 door is ideal for heavy-duty applications requiring protection against the elements. These doors feature a 2″ (51 mm) panel thickness, 16-gauge steel intermediate and end stiles, ribbed steel exterior and 26-gauge steel back cover in a white finish. Polystyrene insulation provides an R-value of 7.35. The Model 422 is a 20-gauge steel door available in sizes up to 29´2″ in width and 24´1″ in height (8890 mm and 7341 mm). 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.