The KOHLER Cimarron toilet tank combines versatile styling with a water-efficient 1.28 gpf flush. Inside, patented AquaPiston technology, a canister flush engine that harnesses gravity to send water into the bowl from all sides, delivers a fast, powerful, virtually plug-free flush every time. Its easy-to-flush canister design takes less force to actuate than a 3" flapper and features 90% less exposed seal material, so it resists the wear, shrinkage, and swelling that lead to leaks over the years.