Abstract: An automatic window includes an inverted U-shaped frame having a pair of window units pivotally supported within the frame for movement between open and closed positions. The combined width of the window units is substantially less than the spacing between the frame side walls to provide clearance spaces which are filled by resilient deformable finger guards on the side edges of the window units preventing injury. A power source acts through a rack and pinion gear arrangement to open and close the window units in unison. A backup locking device secures the window units in the closed positions thereof and deactivates the power source when the lock system is engaged.