Flexize is used to turn an existing vector object directly into a Flex tube object.
If you are familiar with Neon Wizard, "Flexize" is analagous to "Neonize," which converts a vector path straight to a neon tube.
Flexize will use the most recent Flex product when it converts the path to the tube. It is easy to change the flex product by selecting a new one in the Flex Property Bar. The layout will automatically update to the new product, even if you select a different brand.
If you want to remove the flex tube and convert back to the original vector path, select Remove Flex Tube from the Flex Menu.
If you want to freehand draw a Flex Tube, you can also use the Flex Draw Tool.