308 715 01
This upgrade kit is what you need if you have the first generation (2012) ITS-4 wheel and you need to replace your freehub body. In other words, if your wheel was spec'd to use the 308 713 01 freehub body, which has been discontinued, this is what you need. Besides the freehub body and the axle, this kit also includes pawls and springs, end caps, reducers, etc. See photos of details.
Mavic Part #: 308 715 01