These Whiteline heavy duty rear sway bar mounting bracket kits are designed to replace the original equipment with a stronger more rigid version.  Extra heavy duty rear sway-bar mounts improve sway-bar response and should be used for large diameter or adjustable sway-bars.  These mounts are critical when using higher settings as factory mounts will twist and flex and can fail prematurely. 

They also make installation of a larger much easier because they are specifically designed for the larger sway-bar, unlike the stock mounts.