• Complete X1 ball differential set • Direct replacement gear differential • Improves traction in low hold conditions • Improves stability • simpler to drive • Fits X1 Complete ball differential set for the X1 is direct replacement the apparatus differential without any other extra components needed with no extra corrections. Using the ball differential makes the vehicle more stable and more straightforward to drive, specially in really low grip conditions like asphalt or low hold carpet. The ball diff increases on-power steering that will be needed on just about all forms of tracks.