Performance Machine Classic Rear Caliper Kit For Harley Softail Going fast is good, but stopping is even better. Don't trust those stock calipers to tame you high horsepower hog! Upgrade to Performance Machine caliper and know that the most trusted name in V-Twin brakes has your back. Features: Precision machined from billet aluminum 4 piston dual action design for positive stopping power Works with standard 11.5 rotors Utilizes the 1.25 x 4R caliper