The Erie Top Spud Elongated Wall Mount Toilet Bowl, Model 1301-WHT, has a rear outlet with a water surface area of 9"x10". This toilet has a water usage of 1.6gpf/6.0lpf. This toilet is designed for clinical uses, and comes with a 2" top spud that is made to use many different flush valves. The Erie Top Spud Elongated Wall Mount Toilet Bowl, Model 1301-WHT, is made out of a durable vitreous china material, and has a standard china finish. This is just the toilet bowl. The flush valve, flush valve handle, and the attachment screws are sold separately. The Erie Top Spud Elongated Wall Mount Toilet Bowl, Model 1301-WHT, comes with the Mansfield limited 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.