In order to run dual calipers for a hydraulic hand brake with an independent reservoir master cylinder, this bracket allows you to adapt 2 piston Z32 twin turbo calipers to E36M3 312x20 rotors. Installs on the removed drum parking brake's mounting provisions in E36M3 trailing arms, which are a popular swap on non-M cars because of the larger hubs & axles the E36M3 rear trailing arms allow. Compatible with stock E36M3 foot brake calipers and rotors OR Z32 foot brake conversion sold separately. CNC aluminum with gold anodizing, laser logos, and 12.9 grade hardware. Pair with our reproduction calipers, hydrobrake & hard lines and fittings set, all sold separately. Drum parking brtake must be removed.