<P> A dual - flush toilet is a variation of the flush toilet that uses two buttons or handles to flush different amounts of water . </P> <P> The system was proposed by American industrial designer Victor Papanek in his 1976 book Design for the real world, but the first practical implementation was designed in 1980, by staff at the Australian sanitary - ware company Caroma . Although the first generation dual - flush toilet caught on, a redesign in 1993 cut water usage in half compared with traditional toilets, when used properly . The dual - flush toilet has since become almost universally adopted in Australia, New Zealand, Singapore, and Israel, with its use in new buildings often mandated by legislation in those countries . However, due to the more complex mechanism, it is more expensive than many other types of low - flush toilets . </P>

Why is there 2 buttons on a toilet