Shimano Dura-Ace BR-9000 Brake Shoes, which also run under the model name Dura-Ace R55C4, have been designed to be both light and durable. These shoes are intended for use with the Dura-Ace BR-9000 Brake Calipers, though they are compatible with just about every other rim brake caliper you could find. One set include shoes and pads for one wheel. The pads are the BR-9000 Brake Pads, which are intended for standard aluminum rims. If you want to switch back and forth between alu and carbon wheels, youll need to get the R55C4 brake shoe intended solely for carbon rims. They come 1mm thinner and work only with the Shimano Dura-Ace BR-9000 Carbon Brake Pads. The Shimano Dura-Ace BR-9000 Brake Shoes are retro compatible with most of the older Shimano models, including the BR-7900, BR-7800, BR-7700, BR-6800 and BR-6700. They are compatible also with direct mount brake cartridge.