A "must have actually" option for XB4 & XB4 2WD, the ball-differential increases traction and it is recommended for low-traction songs.
The complete factory pre-assembled ball-differential features premium HUDY Spring metal diff outdrives and screw for external adjustment, tough crown gear moulded from high quality extra stiff and dependable self-developed graphite composite combination, high-performance bearings, top-quality carbide axial thrustbearing, heavy-duty diff washers and ceramic 2.4mm diff balls.