The expended energy is stored and used to pull the sash automatically back into the frame after it has been closed by hand - as easy as ABC, similar to a drawer. The all-around night ventilation feature provides for draught-free, consistent and natural ventilation that helps prevent the growth of mould. Turning the handle 180° will set down the sash approx. 6 mm parallel to the frame. When set to this position, the window will remain secured by the locking system. This allows you to conveniently ventilate your rooms even if you are not at home. The ATRIUM® SP komfort comes with bogies and a stay system that are designed for highly heat-insulated window systems.