The door and window system is very important in the whole residential system. It carries the firmness, safety and ductility of the building space. We take the square space as the design language to elaborate, just like an extended interior space, built inward and born outward, and the product system of doors and windows is also a openable barrier connecting the interior and exterior of the space. "The window does not exist as a simple object, but is accompanied by a certain space," Japanese architect Hiroshi Fujimoto said in the trial of the window. The design concept of this case combines the concept of "improving environmental quality, promoting green development" advocated by YKK and the concept of harmonious coexistence of nature. Therefore, the exhibition hall is mainly pure white, with a large area of white space to display products. Change the thinking of products into material forms and integrate them into space skillfully. In the hall, a triangular plane is extended from a point, and the Kushan micro landscape is used. The "few and simple" is consistent with the indispensable function noise reduction of windows. It gives a sense of inner peace.