Kohler 4421-U-0 is a two-piece vitreous china toilet tank with an AquaPiston flushing system, providing a powerful and effective flush using 1.28 gallons of water per flush. It features a left-hand polished chrome trip lever for easy operation and includes the Insuliner tank liner to minimize condensation. The DryLock System aids in quick installation and prevents water leakage. This WaterSense-certified toilet meets EPA flushing guidelines, saving at least 20% more water than 1.6-gallon toilets and is eligible for consumer rebates in some municipalities.