PVC 6x4" Reducer. PVC is Pipe is designed for both above and below ground DWV (Drain, Waste, Vent) Applications. PVC is generally used for both commercial and residential plumbing construction. PVC and its fittings are glued together with special PVC glue that's designed to create a seal that is leak proof and durable like the Pvc pipe. Because PVC is fairly rigid, PVC pipe is an excellent pipe choice for just about any application in the DWV catagory. This PVC 6x4" Reducer is designed for the use in sewer and waste systems. This reducer allows users to decrease the pipe size, and increase the flow and pressure for efficient removal of the waste.