Alcon CAR49: 4 Pot Rear Calipers 31.8/31.8 PairAlcon CAR49 rear calipers deliver the lightweight performance and stopping power demanded by serious motorsport applications. Engineered with a compact 31. 8 31. 8 configuration, this pair reduces unsprung mass while maintaining the thermal stability and modulation required for track use. Alcon's dominance in high performance braking stems from decades of racing heritage, precision manufacturing, and a relentless focus on fade free performance under