Smarter Flush. Suitable for residential or commercial use, the Smarter Flush system converts a standard toilet into a dual-flush model using a retrofit kit. The kit works with any two-piece toilet that has a 2-inch discharge hole, and has been shown to reduce water use by as much as 68% in single-family homes. Additionally, because the kit does not include a flapper, a retrofitted toilet will be less likely to leak, the maker says. When installed, the unit’s Smart Handle gives users the option of a half-flush for liquid waste or a full flush for solid waste. 317.968.9820.