American Standard Cadet PRO 1.28 gpf/4.8 Lpf 12-Inch Toilet Tank with Aquaguard Liner and Right Hand Trip Lever - AMS-4188A155

Tank only. The 4188A155 is the Cadet PRO vitreous china tank, complete with the trip lever and metal shank fill valve, but no bowl and no seat. You order it to pair with a matching 12-inch rough-in Cadet PRO bowl or to replace a cracked or damaged tank on an existing one.

It is built for a 12-inch (305 mm) rough-in bowl, which is the standard spacing from the finished wall to the closet flange center on most North American installs. A 10-inch or 14-inch rough-in bowl needs its own matching tank.

1.28 gallons per flush (4.8 liters), which puts it in the High Efficiency Toilet class, about 20 percent below the 1.6 gpf standard. It still posts a 1,000 gram MaP score at that volume, so the waste removal is at the top of the scale despite the reduced volume. That combination is why property managers use it on retrofits where water use is being cut but callbacks for double flushing are not acceptable.

The oversized 3-inch flush valve dumps the tank faster than a conventional 2-inch valve, which is what lets the Cadet flushing system clear the bowl on only 1.28 gallons. Practical consequence for maintenance: the flapper and valve seat on this tank are 3-inch parts, so a standard 2-inch flapper off the truck will not seal it.

The Aquaguard liner is an insulating lining inside the china tank. It keeps the cold water in the tank from chilling the outer china surface, which is what causes sweating and the puddles on the floor in humid bathrooms. It is a factory feature of this tank, not a kit you add later.

White only, sold under MPN 4188A155.020. If you are matching an existing bowl in a bone or linen finish, this one will not match.

American Standard classifies it as a residential product in the Cadet family. It shows up constantly in multi-family and light commercial work anyway because of the metal trip lever and metal shank fill valve, which hold up better than the plastic equivalents on a high-traffic unit, but the manufacturer's own designation is residential.