Carbotech XP12 has a very strong initial bite with a coefficient of friction and rotor friendliness unmatched in the industry. Fade resistance is in excess of 1850°F (801°C). XP12™ still maintains the highly praised release, excellent modulation and rotor friendliness that have made all Carbotech™ compounds so successful. Carbotech™ XP12™ is not recommended as a daily-driven street pad due to possible elevated levels of dust and noise.Operating range starts out at 250F and goes up to 1850. Friction coefficient is rated at 0.65. We recommend this pad for fast track applications. Fit and Compatibility:Fits Porsche 911 Carrera 2 - 991 3.4L w/Iron Discs REAR factory calipers.