The last dangling shred of an argument in favor of a mountain bike front derailleur is now officially dead. Designed for use with our proven, reliable XD Driver Body, this 12-speed, 10- to 50-tooth cassette offers an optimal 500-percent gear range at a considerably lighter weight than 2x systems. It carries with it the X-DOME architecture, which, independent tests have concluded, yields the strongest cassettes on the market. Shifting characteristics improve both, inboard and outboard shifting, as well as chain retention. XD Driver Body - XD is a cassette driver body design that allows the use of a 10-tooth small cog and provides an improved interface with the cassette. X-Dome - The revolutionary machined design of the X-Dome cassette uses the same grueling manufacturing techniques.
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