Features: Aluminum Steering Arms Left & Right x1 for each These precision, lightweight aluminum steering arms provide enhanced secure attachment, as well as direct steering feel compared to its plastic counterpart with superior durability. Tamiya blue anodized finish. Features built-in ball bearings. Compatible with TD4 chassis cars. Overview: This Hop-Up Option is for use with the TD4 chassis. It replaces the fiberglass reinforced part used in the original kit. The aluminum component raises rigidity for highly responsive steering compared to the standard plastic component.