Derailleur Sram GX Eagle B2 12sp - LunarDerailleur Sram GX Eagle B2 12sp Lunar Riders want the derailleur to do its job shifting on command, whether under climbing load or the stage finish. The GX Eagle derailleur gets it done with an updated cage architecture that improves chain management. Refined to work with the new 10 52t cassettes, its also backwards compatible for the 10 50t versions. Giving riders choice, because thats how it should be. Finished with the new GX Eagle signature