American Standard Champion PRO 1.28 gpf/4.8 Lpf 12-Inch Rough Lined Tank - AMS-4225A154

The Champion PRO 4225A154 ships as a lined tank with the working guts included: a 4 inch piston-action Accelerator flush valve, a metal shank fill valve, and a metal trip lever in chrome. You are buying the tank assembly, not a bare china shell, so for a tank-only replacement you generally just need the tank-to-bowl hardware and gasket plus a supply line to finish.

1.28 gallons per flush (4.8 litres), which is High Efficiency Toilet territory and about 20 percent below the 1.6 gpf federal maximum. It meets EPA WaterSense criteria, which matters if you are chasing a utility rebate or a green building credit on a multi-family retrofit.

Lined means the vitreous china tank has an insulating liner on the inside walls. It keeps the cold supply water from chilling the china surface, which is what causes tank sweating in humid bathrooms or on well water. If you have been mopping up drips under the tank on a hot-summer rental, the lined version of the Champion PRO is the fix.

It is the trade exclusive version of the Champion tank, and the wear parts are metal rather than plastic: a metal trip lever and a metal shank fill valve. Those are the two pieces that fail first in high-turnover rental and hospitality use. American Standard classifies the Champion PRO as a residential product, so it is aimed at apartments, single-family and light multi-family rather than heavy commercial restrooms.

The Champion PRO uses a 4 inch piston-action Accelerator flush valve instead of the common 2 inch flapper. The larger opening dumps the tank faster, which is how it moves waste on only 1.28 gallons. Practical consequence: repair parts are Champion-specific, so a generic flapper off the shelf will not service this tank.

White only, sold under part number 4225A154.020. The trip lever supplied with it is chrome, so if your other fixtures are brushed nickel or bronze you will be swapping the lever separately to match.