Connect 3 in. Sewer and Drain (S&D) pipe to 4 in. S&D fittings with the National Diversified Sales 3P07 3" x 4" White Hub x Spigot PVC S&D Increaser/Reducer Bushing. The drain fitting also connects 3 in. S&D pipe to drainage products compatible with 4 in. S&D connections and 4 in. S&D fittings to drainage products with 3 in. S&D connections, such as select channel drain outlets, drainage grates, and pop-up emitters. This increaser/reducer bushing has a hub and spigot to connect two different pipe sizes. The Increaser/Reducer Bushing is made of polyvinyl chloride (PVC) and makes a Hub X Spt solvent-weld connection. Meets applicable ASTM standards. For use in non-pressurized underground sewer and drainage applications; maximum working pressure of 5 psi. Hassle-free limited lifetime warranty guarantees the NDS product is free from defects—or we’ll replace it.