Paragon 2 Piece Rear Brake Rotors Pair 370x24mm Farewell Goodbye GIFs Tenor. Paragon 2 piece Rotors (Front Pair) for BMW M2 (F87) M3 (F80) M4 (F82 F83) with factory blue BMW calipers. Paragon Performance 2 piece Rotor offers superior braking and cooling efficiency optimized for track and race applications. It features directional ventilation vanes to create suction, turbulence, and guides cool air through the rotor for improved heat dissipation and increased resistance to cracking under harsh track condition. Made of CM 250 special formulated high carbon alloy cast iron, it allows for an optimal bite, thermal characteristics, high temperature strength and durability. Rotor rings are heat treated to release stress in the rotor to avoid deformation and vibration then turned by state of the art CBN surface machining to ensure better break in with new brake pads. Vibration is reduced as the rotor lateral run out is kept within 0. 03mm and well balanced: variations are kept within 2 grams. All rotors went through rigorous quality control procedures and inspections to ensure the rotors are fit for their purposes. The fully floating 2 piece design allows thermal expansion of the rotor while minimizing deformation and ensuring the rotor is self centered with the pads. A slotted rotor improves braking consistency by maintaining a clean contact surface and dissipate heat generated and gases released when the pads come into contact with the rotors. Slotted rotors have a superior advantage over blank rotors in wet or raining conditions by preventing water films to form between the brake pad and rotor surface. Weighing less than most O. E. rotors while maintaining proper thermal capacity, our 2 piece rotors improves overall handling by saving unsprung mass. Aluminum hats are CNC machined from lightweight 6061 T6 aerospace grade aluminum for high strength and durability under extreme track conditions, then black hard coat hard anodized to increase resistance to wear and corrosion. Mil spec Type III anodized hats will not discolor under extreme heat, and are harder and more wear scratch resistant. Unnecessary materials are taken out from the aluminum hats for maximum weight savings while maintaining proper structural integrity. *Black hard coat and hard coat anodized hats are the same in terms of performance and durability. Direct bolt on without any modifications and designed to work flawlessly with OEM ABS and brake system while maintaining factory brake bias. Compatible with OEM brake pads or aftermarket pads with the same pad depth (D) Directional ventilation vanes for optimal cooling performance, runs up to 30% cooler than O. E. rotors and increase cooling efficiency by up to 30%