Campagnolo are the only ones to use this 36mm long freehub body "standard". It was introduced when they released 9 speed cassettes in 1997 and fits all 9 through 12 speed Campagnolo cassettes making it one of the longest-lasting "standards" in the bike industry!
![Freehub Body explanation Campagnolo N3W](https://www.wheelworks.co.nz/wp-content/uploads/2022/12/Freehub-Body-explanation-Campagnolo-N3W-1024x1024.jpg)
![Freehub Body explanation Campagnolo N3W isometric](https://www.wheelworks.co.nz/wp-content/uploads/2022/12/Freehub-Body-explanation-Campagnolo-N3W-isometric-1024x1024.jpg)
Campagnolo 36mm vs N3W
Campagnolo have used the same 36mm long freehub body "standard" since 1997 it fits all 9 through 12 speed Campagnolo cassettes making it one of the longest-lasting "standards" in the bike industry!
When Ekar 13 speed was introduced in 2021 the N3W freehub body "standard" was created for it.
You are able to install a 36mm cassette onto an N3W freehub body with Campagnolo part number HU2AC21N3W but the opposite is not true: There is no way of fitting an N3W cassette onto a Campagnolo 36mm freehub body.
![Freehub Body explanation Campagnolo 36mm vs N3W](https://www.wheelworks.co.nz/wp-content/uploads/2022/12/Freehub-Body-explanation-Campagnolo-36mm-vs-N3W-1024x1024.jpg)