The HB Racing D819 Hub Carrier Arm v2 is a D819 option that allows you to adjust the Ackermann geometry in the steering rack. Ackerman affects how aggressive the car feels. More Ackermann makes the car easier to drive and is better suited to low traction surfaces. Less Ackermann makes the car more aggressive and is better for high traction surfaces. Package includes four v2 hub carrier arms.

The D819 steering block arms are rated no.3 with the least amount of Ackermann - through no.5 with the most amount of Ackermann, and the original "Type 5" arm (HBS111739) being the standard part included in the kit. The arms use dots machined into the top, with a specific number of dots to identify the "no" of arm it is, IE: no.3 arms are marked with three dots.