Since US updated their website they are now able to be added to your chart when you buy your saber it will be the last option at the bottom of the list of drop down menus.
Also sabers that don't come already installed with a covertec wheel like the Aeon v3. From the list of drop down menus you can also pick to have a covertec wheel installed and they will add the extra $14 for installation and covertec wheel.
If your not going to be wanting to hang your saber on your belt, either as a conversation piece or as part of a costume you don't need a covertec wheel or clip.
Covertec Wheel on my Libby (its the silver knob on the saber near the upper left hand side of the image)

Covertec Wheel and Clip

Libby hanging on belt
