Aeroflow competition Ford 9" diff housings allow you to add all of the necessary components for a high-strength rear-end. These housings are made from a thicker gauge of steel than a stock housing, providing more strength and a better base forwelding brackets without housing distortion. With a traditional style notch back cover and reinforced with a CNC machined housing flange that will allow you to weld the axle tubes on the inside and outside for additional strength to reduce axle tube flex. The housings accepts either a 76.3mm (3") or 82.55mm (3-1/4") axle tubes with over 101.6mm (4") of tube engagement. Centre studs are included and installed ready to go.