UM... hmmmm..... are you talking about the body length or the wheelbase length?
The bodies might be different lengths overall but there are only three wheelbase lengths and so far I know of no Xmod that uses the shortest wheelbase length.
EDIT:
No plastic , No paint, just plain old real CF rod!!!
This info is directly from the site I have been buying my CF from.
Carbon Rod (pultruded)
Pull strand solid HT-carbon fiber rod,
unidirectional carbon rovings,
fiber volume content 60-65%
This photo is of a shaft set That I sell.