The new NX Eagle™ derailleur features the proven SRAM 1x-specific X-HORIZON™ design. The larger, 14-tooth X-SYNC™ lower pulley easily facilitates 11- to 50- and 10- to 50-tooth cassette capacity and adds to NX Eagle's overall smooth-pedaling feel. The Type-3 Roller Bearing Clutch™ provides quiet, consistent performance and durability. Details: Model No: NX Eagle Rear Derailleur Series: NX Eagle Cage: Long Speeds: 12 Max Cassette Teeth: 50 Cable Pull Ratio: X-actuation Cage Material: Steel Bearing Material: Steel Color: Black Compatibility: SRAM Eagle 10-50t & SRAM 11-50t cassettes All SRAM Eagle 12-speed chains All SRAM Eagle 12-speed trigger shifters