The E-Z 90° Sewer Adapter has a 3/4" knock-out garden hose connection to drain your second gray water tank into one sewer opening. Use the sewer adatper with #5723 E-Z Coupler Threaded Adapter (sold separately) for a custom fit in female threaded sewers. Durable plastic construction allows long-lasting use. Use for draining your second gray water tank Durable plastic construction for long-lasting use | Valterra E-Z 90 Sewer Adapter in Grey