Abstract: A tub waste overflow assembly that is attachable to a tub wall by means of a threaded retaining body insertable through an overflow drain aperture in a tub wall to engage a cooperatively threaded pipe fitting on the opposite side of the tub wall. A chamfered washer is provided to cooperate with the retaining body and an annular sealing gasket to produce a fluid-tight seal on the interior surface of the tub wall. A forwardly projecting fulcrum member on the pipe fitting preferably contacts the exterior tub wall outwardly of the aperture to facilitate connection of a drain pipe to tub walls over a range of included angles, and no seal is required around the overflow drain aperture on the exterior tub wall. A unitarily molded, knock-out test plug is provided across the bore of the retaining body and a handle desirably attached to the test plug projects into the tub to facilitate installation.