Kohler K-4436-RA-0 Wellworth Classic 1.28 gpf Toilet Tank with Class Five Flushing Technology and Right-Hand Trip Lever, White Class Five flushing technology provides tremendous bulk waste flushing performance and best-in-class bowl cleanliness Canister flush valve provides smooth flushing actuation with consistent water usage, flush after flush 1.28 gpf High-efficiency toilets provide significant water savings of up to 16,500 gallons per year versus an old 3.5 gallon toilet without sacrificing performance Righ-hand trip lever Combines with K-4198 Wellworth elongated toilet bowl to create K-3575-RA Wellworth elongated toilet with 12" rough-in