A Fontana Single Lehar Flush is a type of toilet that uses one flush to clear waste from the bowl. This is in contrast to a dual flush toilet, which uses two flushes, one for liquid waste and one for solid waste. Single flush toilets typically use more water per flush than dual flush toilets, but they are generally considered more straightforward to use and maintain. Fontana Single Lehar Flush is the most common type of toilet in the world and they are widely used in homes, offices, and public restrooms.