12mm Thru Axle for Kid Trailer

12mm Thru Axle for Kid Trailer

(21 customer reviews)

$ 58.00

Robert Axles for Kid Trailers are designed specifically to fit your 12mm thru-axle bike and allow attachment of any hitch-mounted trailer. These fit any trailer that has two wheels and a single point of attachment to the axle. This includes all the two-wheeled child, pet and cargo trailers such as: Thule, Chariot, Burley, Instep, Carry Freedom, and many more.

Purchase our Kid Trailer axle for your bike. Share your stoke for cycling with your kids. Simplify your life by allowing quick and secure attachment of your trailer to your best and favorite bike. Enjoy the adventure.

In stock

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SKU: KID221 Category:


Since 2013, we have been an important part of cyclists’ adventures all over the world. Our axles have millions of miles on them in mountain bikes and road bikes, carbon bikes, fat bikes and e-bikes. Our axles are specifically designed to handle the high-torque loads generated by e-bikes.

Your stock thru-axle is not strong enough to haul your precious cargo! Our axles are 3 to 4 times stronger than the stock axle that came with your bike. Our stainless steel axle ends provide a safe and secure attachment point of the hitch to the axle. The axle is quick to install and remove with a common 5mm hex key.

Our axles are not just designed in the USA, but are made here as well. They are machined by avid cyclists to the tightest standards in the industry. We safety test, to failure, every batch of axles we produce to ensure they exceed your expectations.


Robert Axle for Kid Trailers replaces your stock thru-axle so you can attach a child or cargo trailer to your 12 mm thru axle equipped bike.

  • This axle is compatible with Burley, Carry Freedom, Chariot/Thule, Croozer, Instep, and many more hitch style trailers.
  • The true length of the axle shaft is 167 mm. Please note: Thru-axle lengths do not equal hub standards. An axle has to be longer than the hub to fit in the frame. A 12×142 hub does not equal a 142mm long axle.
  • This axle has a 1.75 mm thread pitch.
  • The axle shaft and axle end are precision CNC machined.
  • The axle shaft is 7075 aluminum and hard black anodized for rugged durability.
  • The axle end is stainless steel, which allow for mounting of the hitch provided with your trailer. The threads are M10x1 (metric).
  • Hardware for attachment of the hitch is included; the hitch is not.
  • No special tools required. Design allows for installation or wheel removal using your standard 5mm hex wrench.
  • Designed, built and quality tested in the USA. Proven around the world.


Need more information about how our axles work?

21 reviews

  1. Sam (verified owner)

    I looked forever for the right sized adaptor, with all of the required specifications. This works perfectly. Thanks so much.

  2. Colt (verified owner)

    The print-out sheet is the perfect way to figure out what axle you need, I got the right axle the first time. It looks and fits great.

  3. DMc (verified owner)

    The axle fit perfectly.

  4. Brian

    It works generally well however tightening the trailer to the axle is pretty cumbersome. Especially with the Burley trailer hitch adapter. The recessed nature of the hitch hanger made getting a wrench on the bolt to tighten to the trailer pretty hard. I wish there would be a redesign to get a socket on the bolt while holding the axle still so it’s not overtightened.

  5. Benji Thunell (verified owner)

    Works perfectly!! We have a Thule Cheetah bike trailer and the mount install/axle swap was as easy as it gets! Killer product!

  6. Zach (verified owner)

    Axle looks to be excellent quality and fits perfect on my 2019 Emonda ALR. Burley’s shorter axle was too long (174mm) for my bike and Thule’s axle required spacer’s for the 167mm size. This one is the right size without spacers for a proper fit and cleaner look.

  7. Mick Occhiuto (verified owner)

    Perfect fit! I’m pulling a Schwinn Rascal with my 22lb. pup in tow. It works great and was super easy to install.

  8. J. M. (verified owner)

    Happy with the selection and buying process. Have only used it a couple if times but so far happy with the build quality. I used it on a 2021 Domaine SL7 pulling a Thule Cheetah Chariot Solo.

  9. Phil (verified owner)

    Works as advertised. I use on a TREK gravel bike with a WIKE special needs bike trailer and the fit is perfect. Nice looking workmanship and prompt service.

  10. Michael Wardlaw (verified owner)

    I am very pleased with the quality product. I purchased a 2021 Trek FX Sport Carbon 4 and wanted to use an Upstand (rear hub kickstand) with my bike. I determined I needed to change the thru axle and was directed to Robert Axle for a remedy. Perfect fit! It cost a little more than I expected, but quality matters!

  11. Camillo (verified owner)

    A solid product that fits and works perfectly!

  12. David Nichols (verified owner)

    I just works as advertised! I bought this axle to pull my burley d’lite double behind a Trek Domane. The website made it super simple to get the right size the first time. The axle is well made and ready to roll!

  13. Alain (verified owner)

    Works perfectly for a 2021 Trek Emonda. Very fast shipping, amazing! Thanks RAP.

  14. Diane Venner (verified owner)

    Amazing service. I emailed to make sure I was purchasing the right axle. Someone got right back to me within a day. Then I ordered the axle & had it delivered the next day & I’m in Canada. It fit perfect & I am very happy.
    Thank you for doing a great job.

  15. Tom Chan (verified owner)

    I am so thankful I came across this website. It solved a huge problem for me. I’m so happy I found a way to hook up my kid’s trailer to my Trek road bike.

  16. Ian (verified owner)

    Works perfectly. Initially, I accidentally ordered the wrong axle. Instead of shipping it, someone double checked my bike and contacted me to say I had likely ordered the wrong axle. And they were right. Thanks that person!

  17. Kevin (verified owner)

    Works perfectly to connect my Burley trailer to my 2020 Trek Domane SL6. Well worth the cost.

  18. Tom Christian (verified owner)

    Worked perfectly, I don’t know why Thule hasn’t made their trailers compatible with thru axles but fortunately these guys sorted it

  19. Erwin (verified owner)

    I have a 2021 Norco Search XR A1 (medium size) and this fits perfectly. No spacers required. Been on a dozen rides and the axel holds solid.

  20. Bettina (verified owner)

    I got this adapter and matching spacers to hook our kid trailer up to my e-bike and it works perfectly. The customer service team helped me work out what adapter and spacers I needed, so thanks for stellar customer service and very fast shipping (to Europe)!

  21. Richard Shurley (verified owner)

    This axle worked perfectly on my Catrike 700. I’m pulling my great-granddaughter in her Burley Bee and she is loving every minute of it.
    The axle fit perfectly and is a quality product.

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All orders from our website are via US Postal Service, from Oregon, U.S.A. We make every effort to ship your order within one business day.

Shipping rates and average delivery times are:

• United States: $7.50 USD, 3-4 business days

• Canada: $21.50 USD, 10-14 business days

• All other International: $21.50 USD, 12-16 business days

We are unable to offer expedited shipping. If you need expedited shipping of our products, please visit our Dealers & Distributors page for options. We cannot take responsibility for any delays during shipping, including delays in customs or incorrect shipping information.

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