The Aquia IV Cube Dual Flush 1.28 and 0.9 GPF Toilet Tank Only with Cotton White is designed for use with the Aquia IV dual flush bowl. The smooth rectangle shape offers a modern and sleek design to complete your bathroom. Features Toto's dual-max dual flush option, allowing you to proactively conserve water usage, allowing you to choose between a 0.9 GPF rinse or 1.28 GPF for tougher jobs. This version of the Aquia tank offers TOTO T40 Washlet®+ and auto flush compatibility for when you are ready to upgrade to a hands-free flush system with an electronic bidet seat. The Aquia IV cube tank meets the standards for EPA WaterSense, and California CEC and CALGreen requirements. The Aquia IV cube includes a tank-to-bowl gasket, tank-to-bowl hardware, and toilet bolt caps. Additional items needed for installation and use must be purchased separately: toilet bowl, wax ring, toilet mounting bolts, water supply lines, and optional Washlet®+ with an auto flush kit purchased separately. The Aquia IV tank should be used with Aquia IV bowls.