These 31 spline inner stub axles are designed to fit Ford 8.8 differentials from the 03-04 Cobra Mustang. They are designed to work with our standard 108mm (930) CV Joint. Must be a 31 spline differential. Stub axles are the same used in our 1000HP Outlaw axles for the 03-04 Cobra. Perfect for diff and cradle swaps.