This is a pack of two optional Mugen Steel Kingpin Balls for MBX7 / 7T nitro buggy & truggy.
These kingpin balls are heavier than the stock parts, and eliminate the need for arm weights.
They will help to improve the steering and handling in bumpy and low traction conditions. When all four kingpin balls are replaced, these will add 21.6 grams of weight to the front suspension.