Abstract: An in-the-wall base unit is provided for connection of building water supply and drain lines to it. A surface-mounted adaptor unit is fastened to the front of the base unit, extends outside the wall for connection of the supply and drain lines in the one instance to a washing machine, and in the other example, to a lavatory. A cover plate neatly frames the adaptor unit and covers the relatively small opening in the wall board through which it extends. A single lever valve assembly controls both the hot and cold water. Build-in drain and vent provisions are made.