Eagle x01 xg 1295 cassette 12 speed take a quick look at the new x dome eagle cassette 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 casset