WhiteLine 22mm Rear Sway Bar: MAZDASPEED 3Part Number: BMR78ZWhiteline's rear sway bar for the MS3 will tighten up your rear suspension. This in turn, will greatly improve handling and your overall grip on the road. The 22mm thickness provides an increase in stiffness of approximately 20% when the swaybar is installed with it's softest setting. However, the adjustability provides stiffer settings, if desired. Whiteline recommends that you always install the swaybar on the softest setting initially, and then adjust it stiffer, if desired.