Camco
If your RV has a holding tank, a sewer hose connects it to a dump station or site sewer connection so you can empty the tank. If you already own a hose in good shape with the right fittings, you do not need another.
RV owners who empty their own tanks.
Camco TST Blue Enzyme Toilet Treatment - Formaldehyde Free - Breaks Down Waste And Tissue - Septic Tank Safe -Treats up to 8-40 Gallon Holding Tanks - (8) 4 oz Bottles (41501) (ASIN B005BNZ3YE). Amazon's page has the current price, specs and reviews.
As an Amazon Influencer, Dude RV earns from qualifying purchases.
Check current Amazon listing (ASIN B005BNZ3YE).
Fine print: The Dude has not personally tested this product. The details on this page come from the Amazon listing and can change; check the listing for the current specs, price and availability.