Half litre glazed ceramic Water Egg Jug. As explained by Jonathan Stromberg and Dolly Knight (www.implosionresearch.com) - the makers of the Water Energisers: " We have learned from the Viktor Schauberger's writings that it is very important to store liquids in opaque egg shaped containers. Because there are no corners and crevices there is no stagnation and disease causing bacteria ae much less likely to breed. Constant convection and spiralling movement keep liquids fresh, cool and healthy.