Shimano's Dura-Ace 7900, Ultegra 6700, and 105 5700 groups are a little different. With these 2009/10 groupsets, Shimano introduced an asymmetric chain design (with different links on the inside and outside). According to Shimano, "optimal" performance is only possible with a corresponding asymmetric chain like the Shimano Dura-Ace CN-7901 10-Speed Chain, Shimano Ultegra CN-6701 10-Speed Chain, or Shimano 105 CN-5701 10-Speed Chain. In our experience, though, any Shimano- or SRAM-compatible 10-speed chain will work flawlessly with these groups.