White UPVC windows are the classics with design style home soft. These windows, however, could also be designed in different colours due to the aluminium attachment clad. The new I-tec insulation technology facilitates continuous insulation in the frame, thus considerably improving thermal insulation. Upon request, Internorm's I-tec ventilation can be integrated in the KF 410. This ventilation system ensures sufficient fresh air and perfect room climate 24 hours a day.