The XB2 ball differential is recommended for many XB2 configurations whenever applied to very-low to medium-traction dirt or clay areas to improve traction. The externally-adjustable ball differential is machined from HUDY Spring metal and is also hardened for extra durability and long lifespan. A high-quality carbide thrustbearing and carbide balls are included for ultra-smooth procedure. The ball differential comes factory pre-assembled.