This is a replacement Yokomo -1mm Tread 4° Graphite Front Steering Hub Carrier Set. This is the standard front steering wheel hub carrier as equipped with the BD8. These carriers are made from lightweight graphite mixed resin composite to provide the necessary strength and steering response for high performance touring cars.
These carriers feature a kingpin axis 1mm closer to the chassis. By combining these with a wheel hub of different thickness, it is possible to finish various steering characteristics by adjusting the scrub radius and changing the tread width.