Abstract: A quick-connect diverter valve for use in connecting existing water faucets and water filtration units in and around a kitchen, or other areas where clean drinking water is desired. The device consists of a body having a movable sleeve adaptor at one end and an outlet opening at the other end. The sleeve adaptor is slidable to allow the body to be quickly inserted onto and held in an annular groove formed on a snap adapter secured to an outlet end of an existing faucet or tap. The body of the device includes a central chamber having an easily operated piston valve member which is slidingly held therein so that upon actuation of an operating member, the valve member is moved in a first direction to allow entering water to flow from the device into a water filter and back from the water filter through a further chamber and out the outlet end of the device.