Flush King

Catalog Item # 20522

Flush King Reverse RV flush valve provides you with the quickest and most effective way to fill, rinse and remove residue from your black or gray holding tanks.

Flush King rapidly refills the holding tank no matter what height of tank or angles in plumbing. Unique design eliminates messy wands and hoses inside the RV by allowing you to reverse flush your tanks from the outside. Powerful performance removes clogs in drain pipes and improves sensor performance for more accurate readings. Four locking hooks provide a tighter seal to guard against leakage. For your convenience, the handle swivels 360 degrees to make hook up and operation easier. The innovative clear barrel allows you to see when the tanks are completely clean of residue, so there is no guess work.

Flush King fits all Trailers and 5th Wheels and most Motor Homes and is not a permanent attachment. Twist on and off, how easy does it get! Connect the Flush King to your RV's sewer pipe and your sewer hose to the valve. Now you are ready to dump, rinse or clean your tanks in one easy operation! When you are finished, simply remove the Flush King and store it away.


  • Removes remaining residue in the gray and black tank after dumping
  • Improves sensor performance
  • Eliminates messy wands and hoses inside the RV
  • Works on Motorhomes, Trailers and 5th Wheel RVs
  • Clear barrel allows you to see the cleaning in action
  • Sanitary and efficient, no other product on the market does a complete job like the Flush King
  • Fills tanks at any height or angle of plumbing
  • Backflow preventer included
  • Non permanent attachment
  • Easy to use and connect

Technical Specifications

1.88 lbs.

Camper's Choice Rating

Reviewer rating of 5 stars based on 168 reviews (5 Based on 168 Reviews)

Add A Review

  • Easy to use (5)
  • Clear to see (3)
  • Cleans tanks very well (2)
  • Have to take off and store (1)
  • There Are No Cons (1)
  • Water hose connection does not point toward valve. (1)

Works Great

by Robert Blanchard – August 12, 2005
5 out of 5 stars

I used it the first time today and it definately works as advertised. No more hose through the bathroom window. Three minutes to f


by Vern Nelson – August 05, 2005
5 out of 5 stars

This Works Great, Our trailer is New & it was our 3rd time out with it & I used this. I could not believe what was left in

You won't be disappointed

by Robert Protzman – April 25, 2007
5 out of 5 stars

Flush King takes the guess work out of knowing if your tanks are really clean. Compared to using a wand this is a no brainer.

Everybody Needs One

by Walter McPhearson – May 29, 2003
5 out of 5 stars

This is absolutely great; gets the 'hidden extras' out of your black tank; very easy and convenient to use on all tanks.

Great Product

by Jeff Williamson – August 18, 2009
5 out of 5 stars

We have a 2001 Cameo by Carriage. We had a clog in the gray water tank. the Flush King worked as advertised. The clog is gone and

The gate valve can rotate around the translucent elbow. Here is a product demonstration for the Flush King.
by Camping World – January 18, 2016
This uses bayonet style fittings to connect into the line.
by Camping World – June 11, 2013