All the metal components on E90 rear suspension are from high strenght steel

Inlet Fitting (30mm) - Suits Turbosmart Kompact Dual Port and Plumb Back BOVs

the GenV Range has more features

Adaptor - Adapts Race Port and Big Bubba Fitting to 38mm Type 3 (grub screw style) inlet fitting

Clutch Kit - Xtreme Performance Heavy Duty Sprung Ceramic Incl Flywheel 940Nm KFD28502-1B Chevrolet All the metal components onXtreme Performance sprung ceramic kit 1B Recommended for: Motorsport ApplicationsThese kits are available with sprung ceramic friction discs and are designed for motorsport applications where higher heat and torque capacity is required. These can also be used in some road applications. Specifications: Torque capacity 940Nm Clamp load Increased over standard Sprung Ceramic Friction Disc Heavy Duty Pressure Plate Kit contains everything you need for a