Any imbalance between the rate of filling of the toilet tank and the bowl can lead to overfilling of the bowl. The excess water due to overfilling of the bowl goes straight down the toilet, literally. Depending on the extent of filling imbalance, the amount of wasted water can be as much as 5 quarts per flush. This simple to install toilet filling valve kit allows you to quickly and easily adjust the rate of fill of the tank in order to match the rate of fill of the bowl.