This is the Level 2 600HP Axle Bar/Outer CV Upgrade for the 2003-2004 Mustang Cobra. The outer CV is a proprietary material with a unique Carbo Ausse Tempering that gives it a very hard shell and it fits the stock wheel hub. These axles feature our chromoly center bars and will re-use the inner CV from your factory axle. Designed to handle 600HP at the wheels, it is one solid axle set. We include the boots, clamps and grease so you can install the inner CV's from your stock axles on the Level 2 axles. Rated to 600HP with a 1-year warranty. Price listed is for both axles.