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Charlotte Pipe 6 in. x 8 in. DWV PVC Pipe Increaser Reducer Bush PVC 00102 1900 - The Home Depot
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Gray PVC Pipe Adhesive Fittings Sleeves Reducers Bend Elbow Tee Ball Valves Caps | eBay
Value Collection - 4 x 3″ PVC Plastic Pipe Reducer Bushing - 89492367 - MSC Industrial Supply