KOHLER K-4899-0 Tresham 1.28 gpf Toilet Tank, White 12" (30.5 cm) rough-in Class Five - provides tremendous bulk-waste flushing performance and best-in-class bowl cleanliness 3-bolt installation - Three-pre-installed tank bolts save installation time 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