The TOTO 1G Glaston 1.0 GPF Toilet Tank is designed for use with the Glaston bowl. Compatible Glaston bowls feature TORNADO FLUSH: A hole-free rim design with dual-nozzles that creates a centrifugal washing action that assists in rinsing the bowl more efficiently. Compatible Glaston bowls also feature the TOTO 1G flushing system that creates a powerful flush with only 1.0 GPF. The Glaston tank comes equipped with a decorative left-hand chrome trip lever. When paired with the corresponding TOTO Glaston bowl, the Glaston tank meets the standards for EPA WaterSense, and California’s CEC and CALGreen requirements. Additional items needed for installation and use must be purchased separately: TOTO Glaston bowl, wax ring, toilet mounting bolts, water supply lines and a toilet seat.