A Scale object generates a percentage scale running from 0% to 100%. A good place for such an object is e.g. below a fuel gauge.
Depending on how much space is available, the scale will be more or less detailed.
Due to MUI's automatic layout system, you don't need to worry about it's size. When placed in a vertical group just below the object you want to scale, everything is fine.
Scale class is often used together with Gauge class. See Gauge class for details.