The Mansfield Alto With pilot valve and 2? flapper Tank 172-BONE is a Bone 12? Rough tank made of vitreous china and is the tank only. It has a water usage of 1.6gpf/6.0lpf due to its quality fixtures. The Mansfield Alto With pilot valve and 2? flapper Tank Model 172-BONE is also affixed with tank trim, tank to bowl gasket, washers, bolts and nuts, and a Matching Trip Lever for the easy installation to the rest of the toilet. The Mansfield Alto With lined pilot valve, and 2? flapper Tank Model 172-BONE 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.