Most Bike Trailers go on a Traveling Bike and although many (travel-) bikes still use the Quick Release axle there are more and more bikes that come with the stronger and stiffer X12 or Thru-Axle.
To connect a Bike Trailer on an X12 Thru Axle we now offer the Thru Axle Adapter from Robert Axle project in our assorment. Your current axle is replaced by a new axle that has a protruding end to connect your hitch on.
To decide which Thru Axle Adapter you need, please use this document.
With an X12 axle adapter you can easily attach a bicycle trailer to an X12 axle