Bosch BP391 QuietCast Premium Semi-Metallic Rear Disc Brake Pad Set Bosch dedicated engineering to platform specific premium materials, ensuring exceptional stopping power and quiet operation with low dust Quiet operation with rubber core multilayer shim provides increased strength and insulation against noise Advanced aerospace alloy used in patented copper free ceramic and semi-metallic friction formula is compliant with 2025 Copper Free legislation Protective transfer layer extends pad and rotor life Slots and chamfers for premium quality, fit, and function; hardware kit (where available) and synthetic lubricant included to perform a complete brake job