These billet E30 Rear Sway Reinforcement Blocks are an ideal upgrade for anyone running or looking to run aftermarket rear sway bars. It's well known, that the OEM rear sway bar mounting bracket is fairly weak causing it to be susceptible to flexing when mounted with stiffer aftermarket sway bars. Our CNC milled billet aluminum rear sway brackets have been designed to never flex and can be adapted to three different sway bar sizes! We offer these for 16mm, 19mm, and 22mm rear sway bars. We include these with all of our rear sway bar kits.