| 摘要 |
The present invention prevents external and internal air from flowing and completely blocks a foreign substance to flow into the inside to maximize cooling and heating effects of the inside and to maintain the inside to be pleasant. An inner window coupled to an inner rail integrally formed on a window frame constituting a window is not to be opened and maintained to be fixated. The inner window of the coupled inner rail is coupled in an exposed position and always adheres to the window frame in a process of opening and closing an outer window coupled to an outer rail of the window frame, thereby maintaining airtightness. |
