a new and improved window assembly includes a window frame , and a window sash having an open - tilted and a closed position . the window sash has pivot pins that engage kidney shaped receptacles located on the window frame . the kidney shaped receptacles permit movement of the window sash into the open - tilted or closed position . the design of the present invention minimizes the parts needed to assemble the window assembly making such a window assembly cheaper to manufacture and easier to assemble .