2Pcs 12T 14T Ceramic Bearing Bike Rear Derailleur Pulley Guide Pulley Roller Idler For SRAM XX1 GX SHIMANO Bicycle Jockey Wheel

specificationBike Cycling Aluminium Ceramic bearing Jockey Wheel Rear Derailleur Pulley 12T,14TGear: 12T 14TBearings: Ceramic bearing.  Stainle shell , durableColour: Blue, Black,Gold ,Red,GreenWeight: approx 14.9gDiameter: approx 50mm(12T)Installation dimension:4/5/6mmMaterial: 7075 Aluminium Alloy body& Ceramic BearingFit For: Shimano Sram 9/10/11/12 Speed bike Rear Derailleur

Copper Adapter: 4mm,5mmFearture:12T/14T teeth bicycle rear derailleur acceary.Made of aluminum alloy, lightweight and durable.A neceary acceary for your bicycle.it is machined by AL 7075-T6 round rod ,finished machined by diamond ,with diamond metal texture and good abrasion resistance index , it adopts ed Japanese steel bearing,rotating without  resistance ,it greatly decreased frictional resistance,and increased cycling efficiency, the design inreased bike derailleur shifting speed ,it causes no noice when shifting speed k and prevent bike chain falling .package:Narrow wide gear Cycling Bike Wheel Rear Derailleur Pulley*2 pc