Wilwood XRZero Brake Calipers combine decades of race experience, computer finite element analysis (FEA), and state-of-the-art machining into a race caliper that is lighter and stiffer, with zero drag. The unique shape of the high surface area body creates a caliper with superior brake fluid cooling and allows more airflow through the rotor. Optimized profile high-temperature seals provide better piston retraction resulting in less drag. The unique center X-bridge strengthens the caliper body without adding mass or obstructing airflow to the brake rotor or pads. Computer FEA design and precision CNC machining of the stress-flow forged aluminum body results in a caliper weighing just 4.66 pounds - 1/2 pound less than a comparable sized Wilwood Superlite caliper.