text: * A rotameter requires no external power or fuel, it uses only the inherent properties of the fluid, along with gravity, to measure flow rate.
  * A rotameter is also a relatively simple device that can be mass manufactured out of cheap materials, allowing for its widespread use.
  * Since the area of the flow passage increases as the float moves up the tube, the scale is approximately linear.
  *Clear glass is used which is highly resistant to thermal shock and chemical action.