The X2 balljoint fits 94-04 Mustangs. It also fits 87-93 Mustangs that are equipped with the Ford Racing M-2300-K Cobra Brake conversion kit or Baer 13" or 12 " American Sedan Brake kits. It will not work with stock 87-93 brakes because of interference between the rotor and the repositioned control arm. Steeda's X2 Balljoint improves suspension geometry on lowered Mustangs by raising the spindle relative to the balljoint pivot-point. This raises the roll center back into the correct range for optimum handling, resulting in reduced body roll, quicker steering response and improved overall front tire grip. Sold as a set of two.