Abstract: A hose connection vacuum breaker backflow preventing device for installation on the discharge nozzle of a water faucet for preventing reverse water flow into the faucet which may possibly contaminate the water supply. The device includes a unitary tubular body defining an unobstructed passageway with threaded female inlet and male outlet connections at opposite ends thereof. An integral shoulder is formed interiorly of the passageway and a pair of exhaust ports open radially outwardly through the body from the passageway upstream of the shoulder. A valve assembly within the passageway is spring-biased into a seated position closing communication between the inlet and outlet ends of the passageway while permitting fluid communication between the outlet end and the ports for draining any reverse water flow.