Dual Washbasin and Cistern

now this is GOOD ECO-Design, and so simple...

Via - renest
The hand basin-dual flush toilet combination has the potential to save a lot of water (70% over an 11L single flush toilet and separate hand basin). You wash your hands with perfectly clean water straight from the same supply that runs to your kitchen sink, and what would normally run down the drain, runs into your tank and is used to flush your toilet instead.
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