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  1. Tow Bar Base Plate
  2. Roadmaster
  3. Removable Draw Bars
  4. Twist Lock Attachment
  5. Partially Hidden
THIS ITEM IS NOT A FIT FOR
2022 Audi S7
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Roadmaster

Roadmaster Crossbar-Style Base Plate Kit - Removable Arms

Part Number: 521878-1
In Stock
$575.00
Retail:$632.50
You Save: $57.50
Tow Bar Base Plate
Not Confirmed to Fit

2022 Audi S7

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etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
Roadmaster's crossbar-style brackets are virtually invisible, easy to mount, and simple to remove. Brackets install on your vehicle's frame to provide attachment points for your tow bar. Great Prices for the best tow bar base plate from Roadmaster. Roadmaster Crossbar-Style Base Plate Kit - Removable Arms part number 521878-1 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (2211)
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Roadmaster Tow Bar Base Plate - 521878-1

Highlights

  • Custom Fit for Your Vehicle: Mounts to existing attachment points
  • Ready for Flat Towing: Mounts to your vehicle’s frame to create secure attachment points for your tow bar.
  • Blends In When Not Towing: Hidden bracket design keeps the front end clean and nearly invisible once arms are removed.
  • Simple Hookup and Release: Twist-lock drawbars install or remove quickly without pins or clips.
  • Built to Last: Computer-cut, all-steel construction with black powder coat resists corrosion and wear.
  • Easy to Mount: No welding required and includes instructions and mounting hardware for straightforward setup.
Made in USA

Features to know about

Built for a Clean Front End: Hidden Bracket Design with Removable Arms

If you like a factory look when you’re not towing, this setup keeps things neat. The hidden bracket design leaves nothing bulky in sight, and once you pull the removable drawbars out, the remaining brackets are virtually invisible. They sit within the grille area where they’re protected from scrapes and scuffs while keeping your front end looking clean.

Fast Hookups and Disconnects: Twist-Lock, No-Pin Attachment

Getting ready to tow doesn’t need to take forever. Each drawbar simply slides in, twists to lock, and you’re ready to go—no pins or clips required. When you’re done, twist the arms back and pull them out in seconds. The straightforward design makes connecting or removing the arms quick and frustration-free.

Ready for Heavy Use: All-Steel Construction with Black Powder Coat

Built from computer-cut, all-steel components, this base plate kit delivers exceptional strength for reliable towing over long hauls. The black powder coat finish resists corrosion so you can count on it to hold up through weather and road grime without losing its integrity.

Simple Setup at Home: Bolt-On Install with Included Hardware

There’s no welding required here—just standard tools and some patience. The kit comes with instructions and all necessary mounting hardware, so the install is straightforward for anyone comfortable tackling a bolt-on project. Once mounted to the frame, you’ve got solid attachment points ready for your tow bar.

Works with Your Existing Roadmaster Tow Bar Setup

This base plate is compatible with Roadmaster tow bars when used with the quick-disconnect crossbar #910021-00 (sold separately). It’s an easy way to integrate into your existing setup without reworking your entire towing system.

Specs

Construction and Design

  • Bracket design: Hidden bracket design provides improved aesthetics compared with standard brackets
  • Drawbars: Easily removable - just twist and pull
  • Attachment: No pins or clips required
  • Construction: Computer-cut, all-steel construction provides exceptional strength
  • Finish: Black powder coat finish is durable and corrosion resistant
  • Installation: Simple installation - no welding required
  • Base plate type: Custom base plates ensure a perfect fit for your vehicle
  • Compatibility: Compatible with Roadmaster tow bars with use of quick-disconnect crossbar (910021-00 - sold separately)
  • Included items: Instructions and mounting hardware included
  • Origin: Made in the USA
  • Warranty: Limited Lifetime Warranty

Features

  • Drawbar mounting and removal: Insert into brackets and twist to lock in place; twist back and pull out to remove
  • Aesthetic benefit: Remaining brackets are virtually invisible when drawbars are removed
  • Mounting location: On most automobiles, brackets are mounted within the grille for protection from scrapes and scuffs

521878-1 Road Master EZ 2 Base Plate Kit

Installation Details 521878-1 Installation instructions

This Product Fits The Following Vehicles




Ratings & Reviews

4.8

2211 reviews
5 Stars
(1864)
4 Stars
(261)
3 Stars
(48)
2 Stars
(13)
1 Star
(25)
Review sort icon
Roadmaster's crossbar-style brackets are virtually invisible, easy to mount, and simple to remove. Brackets install on your vehicle's frame to provide attachment points for your tow bar.

by:

Fast shipping



by:

The installation took me about 7 hours, the facia removal was tedious , between the installation videos and instructions, I performed the task. This bar has one con, the pull rings on the removal bars are flimsy , my first pull stretched one out. I’m sure trailer has a fix for this under warranty, I hope.



by:

The representative (Sarah) was very helpful and knowledgeable, the prices are very reasonable and all my items arrived on time. When I called with a question, she was very polite, friendly and genuinely sounded like she enjoyed her job. When I discovered one of the items I ordered wasn’t needed, getting help to return was hassle free. I would recommend etrailer to anyone that needs anything RV or trailer related. I will definitely do business with them again. I am impressed.



by:

Etrailer was very easy to do business with and made it simple to ship my order directly to the RV shop that was going to install it. This was my first order from them, but I will definitely consider future purchases from them if I'm in need of something for my RV.



by:

We towed our 2004 Subaru Impreza WRX STI 3000 miles last year, this is an ideal setup, discreet when not in use, solid, and easy to get on/off. Very please with the support I received from Roadmaster as one of the bolt was missing, was sent super quickly.



by:

Not an easy install on a Trax but it is very well made and gives a clean look. I did customize by cutting down the 6 pin bracket supports to get it flush with front of the car.



by:

Install pretty easy. You will have to change directions of one bolt due to obstruction ( frame). Cannot torque a few of the bolts. These are the ones with wire attached.
Rock guard needed addition trimming from factory instructions.



by:

Awesome delivery speed, and a well made base plate for my 2007 Element. Installation was a breeze (thanks to my son’s heated shop) and I had to do no cutting to make this fit. I had a Stowmaster tow bar that came with my RV and etrailer was able to steer me to the correct missing parts to make this a really affordable installation. Now to get out of this snow!



by:

I’ve been purchasing products from ETrailer since 2005 and all the products I’ve purchased have been a great value. The products mentioned above installed perfectly and with the direct assistance from ETrailer everything fit as suggested. I will always interact with ETrailer as needs present themselves.



by:

Fit and finish is great, the illustration for what you trim on the bumper isn't great but otherwise pretty easy install (I ended up measuring between the mounts on the draw bar and just trimmed accordingly)



by:

Overall the installation was great, however the process of drilling 3 - 1/2" holes in that little bumper that has a Rockwell Hardness of about 60, seems to be a bit over the top.The instructions are spot on, delivery was great, the quality of product was accurate. I am a happy boy!



by:

Replaced same part that was damaged in a crash. I had used my original one for close to ten years without issue. Fast shipping from etrailer.



by:

The Base plate kit is well made and came with all the necessary hardware.Installation is relatively straight forward. I did have to enlarge two of the holes that didn't quite line up. But overall I'd recommend it.



by:

Bolted right up. Installation should be done with bumper on, as you can't fit the ends through the louvers without some convincing. Works great so far. Was able to use a Stowmaster 5000 with it.



by:

Installation was a bit trying. Ended up looking very clean and almost invisible.
Using the tow bar worked super easy and our motorhome hardly noticed the Mini Cooper back there.



by:

The #118-3 is a perfect fit on my 1995 Geo Tracker. When you pull off the removable arms you would never know they are there. The Quality is very good easy to put on all you have to do is drill 4 holes the tube on the base plate fits into the tube on the frame of the tracker and with the 2 bolts it is a solid fit. I was worried about the plate nut getting it inside of the frame but it went in easy when you put it over the frame tube and use a thin piece of metal to slide it in place. I’m very happy with it. I probably could of got it on without taking my bumper off but with only 4 bolts holding my bumper on it made it easier



by:

Great service



by:

knowledge, professional and very easy to work with. Thanks



by:

The mount was easy to install and fit w ell



by:

Easy install. Well made. Needed a couple of trial fits to get thr gril plate holes cut right, but that is just part of the install. This is easy to hook up for towing. Glad we went with this option.



by:

Fig well

Arnol profile picture

Arnol

6/25/2024

Worked well until I sold the car



by:

Super fast delivery. Product quality looks excellent. I have not installed the base plate yet but it looks pretty straight forward. Interestingly, there was a price reduction on the part between the time I ordered it and the time it was delivered. I brought this to their attention and they immediately processed a refund for the difference. I’ve since ordered another part and Greg couldn’t have been more helpful.



by:

I purchased a Roadmaster tow bar kit from eTrailer for flat towing our Mini Cooper. The kit arrived and is really well built and stout. I installed everything per instruction and right at the end, found the passenger side receiver was crooked, meaning not square to the front of the vehicle. I took pictures and started communicating with Tim in Tech Support @ Roadmaster. This was one of the best experiences I have ever had. Tim used phone, text and email to keep me abreast of his investigation. In the end, he sent me replacement parts straight away and they fit perfectly! I am extremely happy with the purchase and the strong commitment of the Roadmaster company and employees to customer satisfaction.



by:

After ordering the wrong crossbar, etrailer sent the correct one for our Mini Cooper quickly. However I did have to modify most of the holes as the cross bar didn’t quite fit (but close). I had to drill the three main bolt holes to 11/16 so that the bar would go over the Mini’s 3 main bumper bolts on both sides. The two lower bolt holes (each side), needed to be drilled out 3 sizes larger to accommodate the 4 bolts that come with the kit. I had to drill out the Minis lower holes to better align with the crossbars lower holes. I would also like to note it being a pain in the knuckles to reach one of the three (each side) bolts to put the stock nuts on the bolt and then try and get them tight. (The main bolt pattern for the upper bumper is diamond shape, one up tow bolts lower. (The lower “inside” bolt on each side is the one that is hard to get to and tighten.) Sorry I didn’t get picks, I was in a rush to get the car back together. There’s an angle piece on the cross bar that blocks the hard to reach bolt, it would be helpful if that could be made more accessible to reach.



by:

Came quickly and is very high quality. Great directions/video from road master makes the installation step by step easy to follow.
Skill level is probably at the intermediate level depending on experience.

Robert profile picture

Robert

1/7/2026

Everything related to my Mini towing system is working great after a year of use.i do wish I had bought a cover for the tow bar though. Keeping it clean would be easier with the cover. Great products and service from etrailet


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See what our Experts say about this Roadmaster Tow Bar Base Plate

  • Recommended Baseplate For A 2008 Mini 2-Door Hardtop
    Hey John, If you have a 2008 Mini Cooper hardtop S-model or 2008 Mini Clubman hardtop then you'll need the Roadmaster # 521877-1. This will work with Aerodynamic Package, but not with Sport suspension. If you have a 2008 Mini Cooper hardtop base model then you'll need the Roadmaster # 521878-1. This does not fit models with Aerodynamic Package or Sport suspension. If you haven't picked out the rest of your flat towing setup then I have the following recommendations for you: Tow Bar:...
    view full answer...
  • Base Plate and Flat Towing Equipment Recommended for 2007 Mini Cooper
    If your 2007 Mini Cooper Hardtop Base is equipped with a manual transmission, it is capable of being flat towed. As far as ease of installation goes, I'd put them on an even level. Actually bolting the base plates to the vehicle isn't terribly difficult, the hard part is disassembling the vehicle by removing the grille assembly and bumper cover. For ease of use on a day-to-day basis, I'd recommend the Blue Ox # BX1304. The base plate is very well engineered, easier to use because it doesn't...
    view full answer...
  • Parts Needed to Flat Tow 2010 Mini Cooper Behind Class C Motorhome
    The first thing you'd need is a base plate kit that fits your 2010 Mini Cooper which for that we have the Roadmaster part # 521878-1. In addition to the base plates, you will also need a compatible tow bar, safety cables, lighting, and supplemental braking to flat tow your vehicle. The most popular compatible tow bar is the Falcon All Terain, # RM-522. This has non-binding arms which makes the setup very easy to connect/disconnect. For lighting/safety cables, locks, and covers for the...
    view full answer...
  • Recommended Base Plate for a 2009 Mini Cooper Hardtop Base Model
    The correct base plate kit for your 2009 Mini Cooper hardtop base model is the Roadmaster Crossbar-Style Base Plate Kit item # 521878-1. This will connect right to the crossbar on your Falcon 2 Tow Bar item # RM-520. Here are a couple of other parts you will need to flat tow your 2009 Mini Cooper: Wiring Harness - Roadmaster Tail Light Wiring Kit with Bulbs item # RM-155 Supplemental Braking System - Blue Ox Patriot Radio Frequency item # BLU37TR
    view full answer...
  • Parts Needed to Flat Tow 2009 Mini Cooper Convertible JCW
    We have the parts needed to tow your 2009 Mini Cooper Works Convertible JCW but since your vehicle has the turbo engine we don't have a way to flat tow it. Instead you'd to use a tow dolly like the Demco Kar Kaddy # DM9713045.
    view full answer...
  • Recommended Adapters To Connect Roadmaster EZ2 Base Plate to Blue Ox Tow Bar For 2008 Mini Cooper
    It sounds like you need adapters to connect your Roadmaster EZ2 Base Plate Kit # 521878-1 to a Blue Ox tow bar. For most Blue Ox tow bars you can use Adapters Item # BX88178 or Item # RM-032. I have attached an article that lists which tow bars they work for. If you can tell me the exact model of your Blue Ox tow bar, I can make a more specific recommendation. Be sure to check your owner's manual before flat towing your vehicle for suggestions or recommendations. Links with more information...
    view full answer...
  • Recommended Base Plate For A 2009 Mini Cooper
    The Roadmaster Crossbar-Style Base Plate Kit - Removable Arms # 521878-1 is confirmed to fit your 2009 Mini Cooper. The baseplate has a black powder coat finish which is durable and corrosion resistant. It has a simple installation with no welding required. It is compatible with Roadmaster tow bars with the use of The Quick-Disconnect Crossbar # 910021-00 which is sold separately. The Roadmaster Falcon All Terrain, Non-Binding Tow Bar - Motorhome Mount - 2 inch Hitch - 6,000 pounds #...
    view full answer...
  • Which Base Plates for 2009 Mini Cooper Are Compatible With Roadmaster Falcon Tow Bar
    In order to use your Roadmaster Falcon towbar, you'll need to use the Roadmaster Crossbar-Style Base Plate Kit - Removable Arms # 521878-1, which are a confirmed fit on the 2009 Mini Cooper. If you don't have a tow bar wiring/lighting solution for this vehicle yet, I recommend using the Hopkins Magnetic Tow Lights # C6304 , which are easy to install and can be reused if you end up switching dinghy vehicles at some point in the future. I've also linked all of our supplemental braking systems...
    view full answer...

Do you have a question about this Tow Bar Base Plate?


Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Adele M
Updated by:
Adele M
Employee Wilson B
Updated by:
Wilson B
Employee Mike S
Updated by:
Mike S
Employee Isabelle B
Updated by:
Isabelle B

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