SRAM GX Eagle Rear Derailleur - 12-Speed, Long Cage, 52t Max, LunarThe GX Eagle Rear Derailleur gets the job done with a thoughtfully designed cage architecture that improves chain management. Product Details: Mounting system and re positioned Cage Lock offer greater durability Sealed cartridge pulley bearings Specifications: Cage Length: Long Chain Wrap Capacity (teeth): 42 Color: Lunar Drivetrain Speeds: 12 Largest Cog: 52 Rear Der Shifter Compatibility: SRAM X Actuation Rear Derailleur Mount Type: 10x1 Standard