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Featuring the Drain Master 303 Stainless Steel Gearing
Made in Switzerland


Part Name: DM10-MS

Wire and plug lengths approximately 6 inches.

SKU: 5197
Price: $155.73

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Our best solution for emptying your holding tanks. This 3" 12 volt DC Gate Valve is installed on your gray water holding tank and/or your black water holding tank and then opens or closes with the simple push of a button from the LED operator switch mounted at your favorite location.

Kit includes:3" electric gate valve, set of 2 seals, Mate-N-Loc connectors on all electrical wires (wire and plug length combined approx 4"), LED Sensor (pre-mounted on back of gate as shown above), nuts, bolts, Dow 111 lubricant, 1/8" Allen wrench (to operate manual override) and complete installation instructions.

- Dump your tanks with push button ease.
- Add a second switch inside your RV.
- System features L.E.D. open valve indicator.
- Complete system is plug-and-play, making installation a 2-wire snap.
- Gate opens/closes in 1 second flat.

Features a double-sided manual override, including an Allen wrench attached to the valve so it is at hand when the need arises.

Helps you solve your RV holding tank, RV tank, RV toilet, and RV sewer problems.

How to Use:

Full flow 3" ABS gate valve adapts to 3" ABS male or female bolt on specific flange fittings. Can be adapted to most pipe sizes with proper fittings and space requirements. Special seals required for sealing between valve and flanges.

A series of gears allow for a 50:1 gear reduction, developing the necessary torque.

A manual override is accessible from either side of the valve, easily accessible from the dome area.

To activate override, a 1/8” allen wrench is included. There are directional arrows for open/close. Gate is fully opened or closed with a turn and a half on the hex head.


LUBRICATION: Dow Corning 111

Installation Instructions - Pdf Files will open in new window.

General Installation Instructions

DM02-5 Drain Master Product Sheet.pdf (includes measurements)

Note: If installation is going on 1.5” piping, you need to purchase a reducer kit sold separately DM30-CR 1.5” Reducer Kit.

If you need to get Adobe Reader for opening your pdf files, click here to download. Be sure to choose PC or Mac.




"I live in my RV and have been using your electric waste valves for four years.  I hope to never be without them again!  Drain Master Electric Valves have changed my life.  After proper installation, my RV has never leaked.  Dumping black water is now as easy as flipping a switch from the comfort and warmth of the inside of my rig.  I would highly recommend Drain Master Electric Valves to any serious RV' er who would like to expand their enjoyment of camping."

Happy Camping!
Kathy S.



We have a Prowler 5th wheel. Draining the black water was a real problem, I had to crawl under the trailer to pull the drain control. Now, it's a breeze, just push the switch and the black tank is drained. I fill the tank with a hose and drain until I see clear water flowing. We love the Drain Master.

Bob and Joan G.



I would not live without a Drain Master since on my last RV, it was a wonderful thing. I live in a travel trailer now too and have one, and it is just the best invention. I tell everyone about it.....

Debbie H.
Sierra Vista, Arizona



We love our Drain Master valves. They make emptying the tanks quick and easy.

Preston & Bev J.



We are really happy with our Drain Master valves. They make dumping much easier.

Ken & Nola S.


I have an Eagle and it takes 3 valves. They work really, really well. I am so pleased.

Joe & Barb M.



The Drain Master is a great mod to our 97' Sea Breeze. It's really convenient to just activate the switch and dump. I've coupled it with one of those piccolo pipe units that spray water in the tank while we dump. A couple of activations and we run clean and are finished! As I told National RV, the Drain Master would be a great addition to their RV's.


Warren Y.
Cupertino, CA



I've got 2 of them - wouldn't have anything else.

O J.


This is an unsolicited testimonial letter, to thank you for the outstanding service you provided on our RV during our visit to your plant last week.

We were having trouble with the electric dump valve on the black waste tank of our 2005 Phoenix Cruiser.  The key Phoenix executives felt our problem would be best diagnosed and solved by you and your staff – if we were “up” for the 150-mile round trip to Hollister and return to our home on the San Francisco Peninsula.

The purpose of this letter is to tell you-and any interested party-that the trip was well worthwhile.  You not only took care of the mechanical problem, you also provided snacks to tide us over until we could find a spot for lunch.

We arrived at your plant just before noon.  In no more than 10 minutes you and one of your factory mechanics were –literally- on the ground, analyzing our problem.  The two of you worked straight through the lunch hour, until you had replaced both the black and gray valves with your improved version of that part.  It was an important replacement for us because of the improved design of you manual over-ride feature.

You not only replaced both valves which you had manufactured-you also reinstalled a section of the waste line itself, because you noticed it was improperly aligned.

Needless to say, we very much appreciate the way you stand behind your product, and want to thank you for the courtesy and efficiency demonstrated during our visit.  We took off on a 5-day trip to the gold country the very next day and everything worked perfectly.

Thanks again.

Sincerely yours,
Les K – San Mateo, CA



This Drain Master is fabulous! No more leaning down to pull a handle that is hard to move and sometimes breaks in the half open position, making the black waste tank useless. No more repairs on the handle and no more messy hookups.

John G.
Mountain Home, ID



"The greatest thing since sliced bread! No more getting on your knees to open those waste valves, simply push the button and its done. Your trips to the dump station are clean and simple with Drain Master!!"

Nick, All Seasons RV



"Since putting Drain Master in stock, we've experienced great response. We chose Drain Master over other brands because we felt that their design was far superior to the other brands. Also, the service we've received has been outstanding!!"

Brett, Parts Manager
Michael Hohl RV,




"Drain Master will enable me to operate the holding tanks so easily, without bending, kneeling and strain. A bad back and knees made opening and closing the valve very difficult. My toughest job is now my easiest.
Thank you for the great product.

P.S. Your new sewer hose is the best ever!"


Let us know what you think about Drain Master

Can I install Drain Master on my particular RV?
Can the switch be placed outside the RV?
How do I know my Drain Master is installed correctly?
How do I know if the valve is open or closed?
How does Drain Master differ from the other Electric waste valves?
How long will it take me to install Drain Master? Can I do it myself?
Is it OK to install the Drain Master in any position?
How quickly does the Drain Master open or close?
If something happens to the motor, can it be replaced?
What size is the valve?
What if I lose power on my RV, will I still be able to open / close the valve manually?
What kind of switch does the Drain Master use?
How can I use the valve on 1.5 piping?
Where can I place the operator switch?
Will the valve work with the seals from my manual valve?
Is there a warranty on the Drain Master?
What happens if I hold the switch down too long?