Zip ES Compact Electronic Instantaneous Water Heater with Bare-Wire Heating System is the most energy efficient way to directly heat water electrically and heating power is controlled electronically to maintain set temperature with WRAS and VDE approved. · · · The most energy efficient way to directly heat water electrically · · Zip InLine ES provides instant hot water for handwashing · · Double pole over-temperature protection · · Safe operation without the need for a thermostatic blending valve · · Stainless steel bare wire heating element for fast heat up