Shimano XT RD-M8100 1x12-speed Rear Derailleur for 10-51 Cassette Use: MTB Group: XT M8100 Model: RD-M8100 Gradations: SGS-Type 1x12-speed (10-51 cassette) Compatible chain: CN-M8100 12-speed Max. teeth large sprocket: 51T Min. teeth large sprocket: 45T Max. teeth small sprocket: 10T Min. teeth small sprocket: 10T Max. Front Difference: 0T Total Capacity: 41T Pulley cage:Type-SGS long Material:Aluminum/GFRP/Stainless steel/Steel Shimano XT RD-M8120 1/2x12-speed Rear Derailleur for 10-45 Cassette Use: MTB Group: XT M8100 Model: RD-M8120 Gradations: SGS-Type 1/2x12-speed (10-45 cassette) Compatible chain: CN-M8100 12-speed Max. teeth large sprocket: 45T Min. teeth large sprocket: 45T Max. teeth small sprocket: 10T Min. teeth small sprocket: 10T Max. Front Difference: 10T Total Capacity: 45T.
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