Abstract: A unitary boding cylinder which is specially molded from either polyvinyl chloride (PVC) or acrylonitrile butadiene styrene (ABS) for use with a closet flange. The cylinder has a funnel-shaped bore, with a lower end which can be connected to the drainage system, and an upper end, with a larger outer diameter, to which a closet flange can be attached. One embodiment has an upper end with a wall thickness of 1½ inches. The closet flange can be attached directly to the cylinder by threading the mounting screws into the upper surface of the wall. When installing an offset flange, a section of the wall can be cut away to accommodate the angled neck of the offset flange, which is attached to the cylinder, not the concrete slab. A second embodiment, with ordinary wall thickness, can be used for interior installations.

Abstract: A unitary drain waste and vent pipe bushing for reducing the size of polyvinyl chloride (PVC) pipe. The annular body of the pipe bushing has an inner diameter sized to accomodate the end of the smaller-diameter pipe, with an inwardly-projecting stop at the lower end of the pipe bushing. The body of the pipe bushing has an outer diameter sized to fit inside the end of the larger-diameter pipe, with an outwardly-projecting flange at the upper end of the pipe bushing. The pipe bushing allows a plumber to connect the two pipes with only two glue joints instead of three. Because the pipe bushing is disposed inside the end of the larger-diameter pipe, the resulting joint is less bulky than a joint made with the presently-used coupling and insert.