The Toto® Aquia® IV Dual Flush 1.28 and 0.8 gpf Auto Flush Compatible Toilet Tank is designed for use with the Aquia® IV dual flush bowl. The Aquia® IV tank includes a tank to bowl gasket, tank to bowl hardware and toilet bolt caps. The Aquia® IV tank features Toto®s Dual-Max dual flush option, allowing you to proactively conserve water usage. The chrome center-mounted push button that sits atop the tank allows you to choose between a 0.8 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 electronic bidet seat. The Aquia® IV tank meets the standards for EPA WaterSense® and California's CEC and CAL Green requirements. 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 Auto Flush kit purchased separately. The Aquia® IV tank can be used on Aquia® IV bowls.