The SRAM X01 Eagle 12-Speed Rear Derailleur ties the system together, driving precise gear changes across the entire cassette with a titanium spring and durable, forged aluminum body. The Roller Bearing Clutch, long revered for its nearly unbeatable chain stabilization, gets an update with a repositioned upper pulley and larger lower pulley to accommodate the extra chain length needed to run such a wide range of cogs.
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