The Eco Kettle was designed to specifically meet the challenge of reducing the amount of energy wasted when you overfill your kettle. With the Eco Kettle, you can fill the kettle to the brim and simply press the central button in the lid to release a specific amount of water (1-to-8 cups worth) into the boiling chamber. This super efficient and,simple method of accurately guarantees that you boil only the water that you need means that reduce your energy usage while making a cup of tea.