The Mansfield Quantum Toilet Tank Model 153-BISC is a Biscuit 12" rough in tank made of vitreous china and is the tank only. It has a water usage of 1.6gpf/3.8lpf due to its quality fixtures, and flushmate IV technology. The Mansfield Quantum Toilet Tank Model 153-BISC is also affixed with tank trim, tank to bowl gasket, washers, bolts and nuts, and a metal trip lever for the easy installation to the rest of the toilet. The Mansfield Quantum Toilet Tank Model 153-BISC comes with a limited Mansfield lifetime warranty. Mansfield is an American company that?s been in business since 1929, and has been one of the top producers in design, and quality for the past 80 years. They are the largest domestic producer of sanitary ware, and strive to ensure you get the best products available.