Enhance your vehicle’s performance with the premium-quality Performance Machine Rear Brake 125x4R (11). In 1980, Performance Machine pioneered the first 100% CNC-machined brake caliper, crafted from solid aluminum bar. It would take the competition a dozen years to catch up and they have been that far behind since. PM offers a wide range of bolt-on 4 Piston Calipers for the most popular years and models of H-D and other V-Twin bikes. Designed for enthusiasts who demand performance, reliability, and style.