Toto WT151M#01 In-Wall Tank System, 1.6GPF and 0.9-GPF, Cotton Dual-Max flushing system, low consumption (1.6GPF/6.0LPF and 0.9GPF/3.4LPF), Avg. flush 1.28GPF Adjustable 15-Inch-19-Inch mounting height, Saves up to 9-Inch of floor space compared to standard floor-mounted toilet Support up to 880lbs Commercial 2-Inch by 6-Inch or optional residential installation with 2-Inch by 4-Inch wall studs with waste outlet kit 1-pc blow molded polyethylene tank to prevent leaks, 2-Inch by 6-Inch Polyethylene outlet included.Complete with #01 Cotton bolt caps, Pre-plumbed for optional Washlet connection Adjustable 15 inches-19 inches mounting height