The NK2-400 Double is a 2-ply fold-up door. Due to its rigid 400 mm wide frame construction, it is excellent in locations requiring very large doors., e.g. in dockyards and aircraft hangars. The width of a single door can be up to 40 m, and the height 35 m. The door fabric always comes UV-coated, and it is possible to add burglary prevention mechanisms to it, as well. Windows are also available for this door; or the entire fabric can be partially translucent. A touch screen control panel is one of the accessories available for this door. NK2-400 doors are also available with extra insulation.