Composite driveshafts look decidedly different than their conventional steel or aluminum tube counterparts. Composite shafts are carbon fiber wrapped up in a liquid resin that, when it cures, is super strong. What's more, it is much lighter than the aluminum shaft. If you're building a show car that's going to have mirrors underneath, the composite shaft is a showstopper. If you are going racing, it will take darned near anything you can throw at it.