this part here may be required for your application.
Accessory part for these models:
Traxxas aluminum caster blocks improve the appearance, ruggedness, and control on Rustler, Slash, and the Stampede. In addition to the strength and precision of the machined billet 6061-T6 aluminum, the red, green and blue anodized caster blocks feature a high-contrast laser etched TRX logo. Three anodizing color choices are available, fire-red, brilliant-blue and green. Simple bolt-on installation that anyone can perform inspires confidence for future upgrades.