In general, "Totalizer" is used to count the total amount of material (such as fluid) flowing.
In our daily life, we encounter the application of "Totalizer" to some extent. For example, when we go to the gas station to refuel, "Totalizer" will be the key to payment. The we pick up the fuel gun and flip the switch up, the fuel gauge will reset to zero; after refueling, we hang up the fuel gun and pull the switch back down, the fuel gauge will show how many gallons of gasoline we have refueled the payment will be billed based on this amount of gallons .