To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.
Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.
Error submitting comment. Please try again momentarily.
Plug in and go: this permanent system gets you smooth, reliable braking with a one-and-done installation. Low-profile components designed to stay out of sight.
Features:
Specs:
"This is the top system I recommend if you have hydraulic brakes. Quality, reliable, tried-and-true. It just always works."
A braking system is a must when towing a vehicle behind your motorhome. Without it, the weight of the towed car can create a safety hazard, strain your RV's brakes, and affect the warranty of both your car and motorhome. Most states legally require a supplemental braking system, so if you don't use one and you end up in an accident (which is more likely since your RV takes longer to come to a full stop), your insurance and liability headache just doubled. You also won't have any breakaway system; if there's an accidental disconnect, there's nothing to bring your car to a stop.
The Stay-IN-Play Duo is a permanent braking system, which means that it's a one-and-done. Once it's installed, there's no more setup that you have to do. When you plug in the power cord at the front of your vehicle, the system automatically turns on. Flip the on switch for the G-Force controller and just like that, you're ready to flat tow.
While the components are installed permanently in your RV and toad, they remain concealed and inconspicuous. None of them will interfere with normal driving, and most of the time they are invisible. And you don't have to find a place to store them between trips.
The Stay-IN-Play Duo is unique in that it uses both an inertia sensor and your motorhome's brake light signal to activate. Having this double-check ensures that the system will only activate when it's truly needed.
First, the Duo monitors your motorhome's brake light signal so that it knows when you're intentionally hitting the brakes. This ensures there's no false braking.
Second, the inertia sensor in the Duo senses the change in momentum of your toad (towed vehicle) as your setup slows down. It precisely measures this change so it can activate your toad's brakes to match the rate of the RV's deceleration; this is what makes it proportional. When you apply the brakes in your motorhome, the braking system will engage the brakes of the toad at the same time with the same amount of force. This keeps the RV and the toad in sync with each other, so whether it's a gradual slow down to a red light or a hard stop in an emergency, the toad and the RV will brake together.
It starts with the G-Force controller. The G-Force controller contains the inertia sensor that senses the change in your RV's momentum. You'll install it in the cab of your toad, underneath the dashboard. This keeps it out of the way but easy to reach so you can flip the toggle and adjust the knob.
Note: The G-Force controller must be pointed in the direction of travel - with the toggle switch facing the driver's seat - for the internal sensor to function properly.
The controller lets you adjust the sensitivity of the inertia sensor to determine how drastic the change in momentum must be for the system to trigger. Set the sensitivity low and the Duo will only engage when you forcibly step on your motorhome's brake pedal. Set it high and a mere tap on the brakes will get a reaction. It's totally up to you how sensitive you want it to be; a heavier vehicle will probably need more sensitivity, while a lighter one doesn't need to brake so hard. The knob on the face of the controller lets you easily program your setting.
When the G-Force controller detects a change in inertia, it checks that there's a brake light signal from the RV to confirm that it is indeed braking. It then sends a signal to the main operating unit to activate; the main unit delivers pressurized air through an air line to the actuating cylinder that attaches to your toad's brake pedal. The cylinder will pull the pedal down, applying your brakes almost instantaneously.
The actuating cylinder attaches permanently to the arm of your toad's brake pedal. Though it is permanent, it should not interfere with your everyday driving. In most vehicles, it is tucked up where you can't even see it.
When you're driving, your vehicle uses vacuum pressure to create the force needed to bring the car to a stop. On most vehicles, this vacuum-assist function does not work when the engine is off. As a result, a lot of supplemental braking systems have to use an excessive amount of pressure while braking the toad.
The Duo, on the other hand, reactivates the vacuum-assist function by tying into your car's vacuum line. Your car will brake evenly and naturally as it's being towed, so there's less risk of damage.
Included with the Duo is an LED indicator light for safety and peace of mind. This LED, mounted in the toad (on the dash or on the back of the rearview mirror) and visible in your RV's backup camera, will light up whenever your toad is actively braking. It's a simple way to keep tabs on whether the system is working properly or if something is going wrong.
Most supplemental braking systems have a method of letting you know you when they activate, but not all of them are checking if the toad is actually braking. There could be an error that causes the system to activate without actually applying the toad's brakes. Or your brake pedal might actually be continuously depressed when it shouldn't be. But unless you have a system that's monitoring your vehicle, you won't know it until the damage is already done.
This braking monitor connects directly to your toad's brake light switch so it only lights up when the pedal is depressed and a signal is sent to the brake lights.
If there's a strong glare on your toad's windshield, the LED light strip might be hard to see. The wireless Coachlink system (SM99945 - sold separately) is a great solution to this problem; the monitor mounts right on your motorhome's dashboard so it's directly in view. This is a great add-on for convenience and peace of mind.
The Duo also comes with a breakaway switch, an absolute must for safe flat towing. If there's ever an emergency situation where your toad becomes detached from the motorhome, the breakaway switch will immediately activate the brakes and bring the vehicle to a stop.
This switch mounts to the front of your toad and wires into the Duo's operating unit. It includes a pin that connects to your RV's hitch receiver with a breakaway cable. If the toad and RV become disconnected, the cable will pull the pin out of the switch and trigger the braking system. A reserve air supply in the operating unit will then apply the brakes in the car.
Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up.
To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.
| For the RV | Between the RV and Towed Car | For the Towed Car |
|---|---|---|
| Hitch | Tow bar | Base plate |
| Wiring plug | Safety cables | Braking system |
| Wiring adapter cord | Wiring kit/diodes |
The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome.
Customer Satisfaction Score:
94% were satisfied with this product
6% of customers were not satisfied
Ratings & Reviews
I installed this in a 2012 mini Cooper S. With the turbo charger there is no room in the engine compartment for the system unit, so I mounted it under the passenger seat. I had to remove the seat, cut out the carpet, mount the unit, and then buy longer seat attachment bolts. I used half inch thick spacers between the seat track in the floorboard. Made a long run for the vacuum hose to get up to the engine compartment through the firewall. By removing the cowling on the driver side, it exposes a huge Gromit where the main wiring harness passes through the firewall. It actually had two nipples ready to be cut off to run the vacuum hose and the wires through — so that part was pretty easy.
I haven’t towed it behind the motorhome yet, but it passed all the start up tests the first time!
After doing much research and reading many reviews and watching a lot of your instructional videos I chose the Stay-in-Play Duo. It came complete with instructions and extra parts for any application. I like the fact that after everything is installed it is just a matter of flipping a switch and checking it out and drive off. I mounted it in a 2018 Jeep wrangler, not very much room for the operating unit, but I I went off of one of your videos on a 2017 Jeep Wrangler Unlimited and mounted it underneath above the cross frame below and behind the radiator but still protected from the elements. Not a lot of room under the dash either, but everything is in and looks great and ready for the 1st trip.
I had my local Cadillac dealer install the braking system in my Mini and it was done perfectly. Now I just flip a switch and the braking system is activated. I did have them hook up an extra wire on the RV harness. They ran the center 12 volt source to the Mini battery. That way, the system doesn't drain the battery on long hauls. An interesting side note: the system takes an extra half second to release the brake pressure to the car after my RV brake pedal is released. Therefore, if the pressure is set too high, you feel the car putting significant drag on the RV. This really helped to setup the system initially and is a daily reminder that the system is working as a little bit of drag for a half second is normal.
I personally installed this on my 2020 Jeep Wrangler and have towed it using this braking system over 4K miles and have had zero issues. Would definitely recommend! The installation instructions were well written and included an easy to read wiring diagram making is easy to install and the very knowledgeable etrailer support was a bonus too!
I installed the Stay n play on a 2017 Jeep Cherokee Trailhawk. I pull it with a Diesel Sprinter, and braking control is very important to me. Previously I used a Brake Buddy. The Demco system is a world of difference. The proportional braking, simplicity of design, ease of engagement/disengagement, and reliability have provided an improved sense of confidence and security when flat towing. Installation was a challenge but is well described in instructions and videos.
The Demco stay-n-play braking system has worked flawlessly for a full season of towing! The one time installation went smoothly and all components fit and functioned perfectly.
Very easy to use, connect to tow vehicle, flip a switch, and it's ready to tow. Disconnect from tow vehicle, flip a switch, it's ready for normal driving.
Would highly recommend this setup over other braking systems.
Installing on 2020 Jeep Trailhawk :
Pic #0557 : Roadmaster Base Plate Kit , Demco Supplemental Braking System , Diode Wiring Kit , Demco Battery Charge Wire Kit
Pic # 0548 ,0551 , 0559 Had to adjust the bracket plate to line up with the upper bolt holes
Pic #6028 finished install , mounted the operating unit to the top fuse box cover using automotive Velcro . Air cylinder , controller and LED light installed . Aside from the base plate bracket not lining up with the upper bolt holes I would give it 4 stars . My son in law is a master at solving mechanical issues .
I chose to go with this unit because I didn't like the idea of the other types that mash the brake pedal without any vacuum assist & the fact that you have to remove, then reinstall them each time you want to use the car.
This ended up TOUGH install. Not because of the unit, but rather the lack of ANY room under the hood on my 2003 Subaru Outback Wagon to mount the operating unit. The only place I could find that would be out of the way was under the driver's seat of all places! Luckily there was JUST enough hose with the unit to reach all the way to the brake booster. I had to cut the carpeting so the seat would clear the operating unit during movement without any chance of contact. There was no hole in the firewall large enough to accommodate the hose so I had to drill a hole for that although I was able to route the wiring through a small rubber grommet. Routing the hose to the firewall was a real challenge! I ended up running it through the heater duct under the driver's floor mat to the left side kick panel, then up over the pedals keeping clear of any moving parts. WHEW!!
The brake pedal actuator went on without much fuss, although with my large feet I have noticed I'll catch the actuator with my toe on occasion. I may mark the location it's in now & merely raise it up a tab in between trips.
The wiring was pretty much straight forward, there was plenty of included wire & I had JUST enough room tho mount the G-Force Controller on the left kick panel covering without interfering with my feet.
The breakaway switch I fastened to the body in front & below the radiator.
I read where everyone was saying you need to have a battery cut-off device to keep the braking system from draining the battery over time, but I had power from the RV keeping the battery fresh so I didn't worry about that & saved myself the $180 for the cost of an automatic battery disconnect.
After installation, I sat in the car while we towed it around the neighborhood to see how it worked & made the necessary adjustments to the G-Force Controller. Now THAT was weird! What with the car steering itself & braking too.
We just got back from a 4,000+ mile trip & everything worked fine. On occasion I forgot to flip the switch to turn the system off, but it didn't seem to make much of a difference.
All in all a great system!
It wasn't easy to get everything installed in a way that looked neat and professional but in the end the ease with which you can hook up the car and start towing makes it worth it. I bought a replacement factory vacuum pump line so that I didn't have to worry about ruining the original one and as a result the installation looks that much better. Literally all I have to do is flip a switch once the car is connected and I'm ready to go. Given a second opportunity to do the installation I would mount the LED light strip vertically on the backside of the rear view mirror to make it a bit more visible but other than that, I'm happy with how it turned out and the system works great.
System was very straight forward with good instructions. Took a couple of hours to install and worked as designed with not problems. Driving a 2020 Entegra 36U pulling a 2023 Rubicon and this beats dollying any day. Highly recommend this product. 55 yr Master Tech.
This system has worked flawlessly now for a year. I’m quite pleased with it and highly recommend the Demco Stay-IN-Play Duo Flat Tow Brake System. It’s been perfect for our ‘15, F150, FX4, Crew Cab, behind our motorhome.
It was not a simple setup though. It took a few days, a good friend, lots of manual reading, YouTube tutorials, and a couple of phone calls to Demco and etrailer to be certain it was assembled, by us, correctly. If you’re not mechanically savvy, I highly recommend having it professionally installed.
I mounted this in a 2014 Chevy Spark. Finding a spot for the main control unit was interesting, but I found a video for a 2017 Spark that I could use. I did have to drill an extra hole in the mounting flange and car. I haven't taken it on a trip as of this time, but a tow around the block indicated it was working. One note, watch about placing the LED indicator behind the tinted part of the toad window. It makes it harder to see from the camper camera.

Dale
4/17/2024
We are very pleased with this system. We hauled the Spark on a 5,000+ mile trip out west and the brake system did its job. I did tweak the setting a couple of times to get it as I liked it. As noted in my initial post, I still have trouble seeing the LED indicator behind the tint if the windshield, especially in bright sunlight.
Well thought out design. Work great for my 2014 Honda CRV. Youtube gives a great tutorial on the installation even though I installed the cables and hoses a little different, which was harder but I feel looks better
Haven't actually had the chance to tow behind yet so this is just for the install. It took me quite a long time to install but, that's not the products fault. Everything you need to do the job is included.
I only give it 4 stars because the system uses the towed vehicles battery to activate the vacuum/compressor pump, so it would be possible to run the battery down as there is no charge circuit from the towing vehicle. I did choose to add one though. Other than that I'm sure it'll work fine. It was installed on a 1983 Vanagon.

David
10/21/2021
Im not in the car when it works, but the indicator light comes on so I assume they work. Honestly, my motorhome is so big I cant tell if there working or not, mostly I stalled to be legal and safe. I like it.
Thanks to installation videos provided by etrailer, I felt confident that I could do the install myself. I had never pulled off moldings and panels in a car before, but with your videos as guidance , it was a breeze. This system was going into a 2016 Ford Edge 3.5L AWD and your (and SMI's) instructions call for installation of 2 check valves. After calling SMI to clarify the install points, it got even easier, as only one valve is required, and is ridiculously simple to install it. No cutting of original car hoses required (see photo). After everything was installed, the whole setup just simply worked, no troubleshooting required. That was fun and it is totally doable, even for the average guy like myself.

Herbert M.
7/13/2018
The rear-view camera display in my RV is not good enough to show the operation of the brake notification LED which is applied to the rear-view mirror in the towed car. I installed a small light in the RV dash and ran wiring all the way back to the toad, with a disconnect plug at the hitch, of course. Now it is easy to see when the car brakes come on. Else, the system works great.
My husband installed this himself and it took a couple of weekends to finish. It works great and was the perfect solution for our flat-tow set-up.

Heather A.
2/21/2025
Your setup looks awesome, where are you headed with the dinghy?
It's a great system, 3rd one I bought for this now my 3rd jeep.
Instructions are great, video was very helpful.
I'm very pleased with this Stay-in-Play /DUO Braking System which I installed on my 2005 Jeep Liberty. I debated wheather I dared install it myself, but with the video instructions I decided that I could. I watched the video a couple of times, then followed it step by step during the installation, and it went pretty smoothly. One issue I had is that they changed the instalation of the LED indecator light, since the making of the video, so the parts did not come as described on the video. I do prefer the new method, as described in the installation manual, but it does require a toggle switch to turn it off. I installed one just below the Control Unit inside the car (see photo). I was also very impressed since, right after ordering the system, I found it for less on another web site. I emailed eTrailer about my disappointing discovery, and they credited me back the difference. GREAT COMPANY!

Robert P.
12/9/2019
One year later, the system is still working great. Still very pleased.
Works great! The install was pretty simple, with the how-to video being very easy to follow along with. Thank you for all of your help along the way!! I absolutely recommend eTrailer to everyone!

Matt
1/27/2026
Couldnt be happier with the braking system! It was easy to install 23 Jeep Wrangler 4xe and even easier to adjust its sensitivity. I could definitely feel the difference while pulling the jeep behind my 30 RV. 1010 would recommend
I would have given the product a 5 except for 2 things.
The photos that are used in the instructions are almost useless and I expected a little better quality in the break away lanyard and carabiners for the price.
The video that they have for installation on a 2014 CR-V was a life changer. The hookup for the notification light on the mirror has been changed a little. You no longer have to plug and unplug it when you are using the system.
I wish I would have paid a little extra and gotten the wireless coach notification.
The Demco Stay-In-Play is perfect for our towed vehicle setup. I don’t need to manually setup the braking system every time we hook up the towed vehicle. What a great system! Shipped direct to our installer in a very timely manner and the price was fair.

Ron
12/20/2025
Having the braking system built in is so much more convenient than having to install a brake inside the car when we want to go somewhere. Really like this set up.
Shipping and tracking was great the package arrived on time. I haven't installed it yet that's my project for tomorrow

Mark
4/12/2026
After installing it we have used it multiple times and it works great I love that I only have to flip a switch and Im ready to tow without having to recalibrate every time I hook the car up for Towing. Its a great product
This is the 2nd Duo Demco Stay IN Play Flat tow brake system I've purchased. Ive tried other brake systems and wasnt happy. The Duo Stay IN Play system worked so well on my 2021 Jeep Gladiator that I decided to purchase the same system for my 2025 Jeep Wrangler Sport.
Still in the process of installation, but just need to install the interior components (g force sensor & brake pedal actuator). Demco doesn't mention anything about needing a charge line from the towing vehicle to keep the toad battery up to run the compressor/vacuum pump unit. The Jeep I'm installing this into does have vacuum assist power brakes.
Unless you are one heck of a backyard mechanic, let a pro do this. I'm a mechanical engineer and an auto mechanic so I know what I'm talking about. I'll let the pics speak for themselves. And a useful hint: there is a slight delay when you hit the RV brake before the toad brakes come on. Knowing this, I lightliy hit the RV brake pedal to turn on the Duo compressor. Just so you know where I'm coming from, our first use of the Demco base plate, tow bar and Duo was a trip from Colorado to North Carolina. Trip specs:
2301 miles, towing a 2018 Ford F150 XLT Sport 4X4 crew cab behind a 2019 Thor Quantum 28SE with the terribly underpowered Ford V-10.

Christopher H.
8/4/2026
Thanks for your feedback and really appreciate the photos. Definitely agree that an install like this is better left to a professional.
Do you have a question about this Flat Tow Brake System?
Info for this part was:
At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.





























































Wayne S.
4/29/2025
Love the Demco Braking System - i was so much easier to use than the large portable brake that goes in front of the drivers seat. It worked flawlessly and, since I have just sold the car, I definitely will buy another for my new TOAD!