limited to the open window

That is, the window can be opened from above, the open part is suspended in the air and fixed with the window frame by hinges. Called on the suspension. Its advantages are: both ventilation, but also to ensure safety, because there are hinges, the window can only open ten centimeters of the seam, from the outside hand does not come in, especially for no one at home when used. This function has not only limited to the open window, sliding window can also be suspended on the open.