Box position
Sets the box’s x and y position, in pixels. Drag or type either value. See Using the panel for how dragging and typing work, including moving between the x and y fields withTab.
Box size
Sets the box’s width and height, in pixels. Width and height can’t go below 1px.The height field is locked whenever auto-fit is turned on, since After Effects is calculating the box height automatically in that mode. Turn auto-fit off to set an exact height yourself.