The KOHLER Highline toilet tank features innovative Revolution 360® technology, an advanced flushing system that uses a powerful swirling motion to thoroughly rinse the bowl. This water-efficient toilet tank also utilizes innovative AquaPiston® technology, a patented flush engine that delivers a fast, powerful, and virtually plug-free flush. A 1.28-gallon flush provides significant water savings of up to 16,500 gallons per year, compared to a 3.5-gallon toilet, without sacrificing performance. Kohler®, 44467-0, Tank, Transitional, Highline Collection, 1.28 gpf Gallons per Flush, Left-hand Trip Lever Flush Handle, 12 in Rough-In, Bowl Mounting, 15-1/8 in Height, 18 in Width, 8-1/2 in Depth, White