Cruz produce a range of kits for cars with flush roof rails. They all fit in a slightly different way. You'll need to refer to the instructions for the kit you are using. These instructions are supplied with the fitting kit. You can also find them on the 'fitting instructions' tab for the roof bars on our website. You may also find these videos useful.
This video shows how to fit Crux FIX bars:
This video shows how you fit the shorter Fuse bars:
These videos are designed to be used in conjunction with the fitting instructions for your roof bars.