Abstract: A dual flush system tank adapted to provide either a full flush or a partial flush at the option of the user. The control handle is actuated normally to produce a full flush. If a partial flush is desired, the control handle is held in its depressed condition for two or three seconds after which it is released. This produces a partial flush. A partial flush is produced by a buoyant reseating weight which will float down with the falling level of liquid in the tank to depress the flush ball and prematurely reseat it in its outlet seat when only part of the liquid has been discharged from the tank. The reseating weight is provided with a latch actuated by the flush handle. For a full flush, the latch is released but is immediately re-engaged before the reseating weight moves downwardly in the tank and is hence latched against premature seating of the flush bal.