Hella 355120811 Two-Piece Vented Disc Brake Rotor 340mm

The Hella 355120811 is a high-performance two-piece disc brake rotor designed for BMW applications requiring 340mm rotors. This premium braking component features an advanced two-piece construction that separates the rotor disc from the aluminum hat assembly, providing superior heat dissipation and reduced unsprung weight compared to traditional one-piece designs.

Key Features:

• Two-piece design with zinc-coated gray cast iron disc and lightweight aluminum hat
• Vented rotor construction for enhanced cooling and consistent braking performance
• 340mm outside diameter with 30mm nominal thickness for high-performance braking
• 6 x 120mm wheel bolt pattern specifically designed for BMW vehicles
• 79mm hub size with 73.20mm mounting height
• Zinc coating provides corrosion resistance and extended service life

The two-piece rotor design reduces heat transfer to the wheel hub and bearing assembly while allowing the rotor disc to expand and contract independently during thermal cycling. This minimizes stress and extends component life. The gray cast iron disc material provides excellent friction characteristics and wear resistance, while the aluminum hat reduces overall rotor weight for improved handling response.