Mavic makes swappable freehub bodies for most of their rear wheels so you're not permanently married to either SRAM/Shimano or Campy. You can start off with one body with its unique splines, and you can switch to the other fast. The bodies are known in Mavic-speak as FTS-L, or Force Transfer System-Light. The body is made of steel, as you'll currently find on all of Mavic's road wheelsets. In the recent past, most have had the FTS-L as well, save the Aksium. The M-10 is the Shimano /SRAM -compatible body.