... 2.Only 3 seconds for hot water.no preheating,no wait. 3.Thermostatic 4. ... Energy saving 1.Key Features:1) On demand hot water in just 3 seconds. No preheating, no wait.2 ... ) National patent heating technology. Water is completely seperated from electricity.3) Use Ni-80 as ... the heating element, will never form water scale4. Very high heating transfer efficiency, about 99%, ...