Abstract: A device for conserving water used in a conventional water closet comprises a heavy metal cylindrical disc having parallel opposed surfaces and an eccentrically disposed hole extending parallel to the axis. A slot extends radially from the exterior of the device to the hole, which has a smooth bore. The slot may be provided with one or more bosses and cooperating notches in the opposed faces thereof, to enhance the clamping action of the device. The device may be placed with the water closet tank ball valve stem extending normally through the slot, and secured thereon by crimping the device to close the slot faces together. Alternately, the flush valve stem may be disposed through the eccentric hole, and similarly secured by crimping. In a further embodiment the pull chain of a flapper valve may be secured in the device. The added weight of the device causes the flushing action to cease upon release of the flush handle, thereby reducing the amount of water consumed by the water closet.