Wilwood 120-17200-RD Radial Mount Brake Caliper - XRS4R 4-Piston Red

The Wilwood XRS4R Radial Mount Brake Caliper (Part No. 120-17200-RD) is a high-performance, 4-piston racing caliper finished in a striking red anodize. Engineered for serious motorsport and performance street applications, the XRS4R delivers exceptional stopping power, rigidity, and low weight through Wilwood's race-proven design philosophy.

Key Features:

• 4-Piston Design: Symmetrical, opposed 4-piston configuration delivers balanced, consistent clamping force across the brake pad face
• Radial Mount Architecture: Radial (axial) mounting provides superior caliper-to-upright rigidity, reducing flex and improving brake feel and modulation
• Lightweight Aluminum Body: Precision-machined from high-strength aluminum alloy to minimize unsprung weight without sacrificing structural integrity
• Thermlock Pistons: Thermal barrier pistons reduce heat transfer from the rotor and pad into the brake fluid, protecting against vapor lock and fade
• Type III Hard Anodize Bore Finish: Piston bores are hard-anodized with an aluminum-oxide ceramic finish for long-term durability and corrosion resistance
• Single-Point Bleed Technology: Low-profile bleeder screws and single-point bleed design simplify bleeding and routine maintenance
• Red Anodized Finish: High-quality red anodize provides a distinctive appearance and additional corrosion protection
• Wilwood BP-10 Brake Pads Compatible: Designed to accept Wilwood's range of performance and racing compound brake pads

The XRS4R is built to perform under the demanding conditions of road racing, autocross, and high-performance driving events. Wilwood's finite element analysis (FEA)-driven design process ensures that material is placed precisely where it is needed — reducing unnecessary bulk, improving cooling airflow, and minimizing caliper deflection under hard braking. The result is a caliper that delivers consistent, race-quality performance lap after lap.