SwissStop EXOTherm2 Brake Pad Set, Disc 27: for Shimano 4-Piston and Downhill "H" ShapeEXOTherm2 combines an extremely durable, smooth modulating pad compound with a cooling fin equipped back plate which provides consistent, powerful braking in all conditions. The EXOTherm2 technology is SwissStop's maximum pad life compound that also offers minimum brake fade Organic compound provides a low pad wear rate Aluminum backing plate is equipped with cooling fins for heat dissipation and is lightweight Smooth, consistent brake performance