The Kinetic Traxle is a precision-machined replacement thru-axle with tapered heads that stand out just far enough from the bike frame to perfectly fit trainer cone cups. Traxles adapt any 12mm thru-axle system to firmly lock your bike into a trainer. Specifically engineered to work on Kinetic trainers, the system also works with most other trainer brands making it a perfect solution for bike shop fit stations or home use. To determine which Traxle you’ll need, follow the steps below. If you don't know if you need a Traxle or not.

Sizing guide found here

https://static1.squarespace.com/static/587795e1725e25a56602aafe/t/589ce44fd1758e56544fe0ce/1486677071731/Traxle_SizingGuide.pdf

For fitment

https://www.kurtkinetic.com/thru-axles