The key feature to the performance of the showerhead  is the screw like turbine device shown.  When the water stream reaches the shower head it rebounds from the underside of the “screw” and is retained in an expansion chamber, where it builds up pressure. When the pressure reaches a certain level, the water bounces back and out of the chamber many times per second. This pattern uniquely manipulates the surface tension of water.  Without choking the water flow, this action maximises the effect of every drop, maintaining pressure and temperature whilst consuming much less water but achieving the performance of a much greater flow. There is no attempt to give the illusion of more water by filling water droplets with air - just fuller droplets, delivered with propulsion and impact.  View Technical Story   for further detail and background. View  Technique Movie for an illustrated explanation.