Materials: Titanium Gr2,Gr5(6Al4V),Aluminum 7075-T6,6061-T6 Spec: 10t 11T 12t Treatments: Polished,Anodizing Titanium Ti Jockey Wheel for Rear Derailleur Pulley 11TMaterials: Titanium Gr2,Gr5(6Al4V),Aluminum 7075-T6,6061-T6Spec: 10t 11T 12t Treatments: Polished,Anodizing(Blue,Gold,Red,Black green)