The top rail of the bottom Sash and the bottom rail of the top Sash in a Double Hung window. These rails meet in the center of the window when window unit is in closed position. Check Rail equipped with either vinyl or rubber "bulb" weatherstrip.
Horizontal members of a double-hung window which come together.
The horizontal members of a tilt double-hung sash that meet, and the vertical members of a slide/by sash that meet.