Caroma's DuoSet toilet is a two button flush system allowing the user to select between a 9 litre and a 4.5 litre flush. The clear acrylic cistern is a specially made demonstration model to show the internal mechanism.
The Caroma dual flush toilet was developed in response to Australia's limited water resources. The introduction of the 9/4.5 litre flush system in 1980 reduced water use from an average 55 litres per person per day to 27 litres per person per day. As a result dual flush toilets were made mandatory around Australia in all new buildings. Caroma redesigned the cistern and pan in 1994 to produce an even smaller 6/3 litre product which reduced water use to 18 litres per person per day.