You always take the right decision with KF 410 - be it in classical UPVC white or with weather-resistant aluminium clad. The square-edged design of frame and sash matches the design style of home pure. Due to the new I-tec insulation technology, the frame is insulated continuously and thereby thermal insulation is improved considerably. Upon request, I-tec ventilation can be integrated into each window. This innovative ventilation system ensures sufficient fresh air and perfect room climate 24 hours a day.