This dispenser is designed to make reconstitution efficient and convenient. After turning on the system, the amount of water needed is selected and dispensed when the dispense button is pushed. The system initially provides half the water, for shaking purposes, then the rest is dispensed after pressing the dispense button the second time. The system fits into the existing water supply line and the four-stage Reverse Osmosis (RO) filtration system ensures the dispensed water is free of particles that may be present in the water supply. Included in box: FillMaster 3400 System, 2.1 gallon tank, four-stage RO system, air-gap faucet and installation hardware.