Bicycle Bike Rear Derailleur Ceramic Guide Pulley 12T Positive and Negative Tooth Guide Wheel Cycling Bike Ceramics Bearing Guide Pulley

Specifications:
Material: CNC Aluminum alloy+Ceramic; 
Color: Black, Blue, Red, Gold; 
Diameter: 55mm; 
Thickness: 8mm; 
Type: 12T; 
Weight: 12g; 
 
Features:
12 teeth bicycle rear derailleur accessary. 
Made of CNC aluminum alloy, lightweight and durable. 
Setting for 4/5mm spindle shaft rollers. 
Adopts  ceramic  bearing, rotating without resistance, it greatly decreased frictional resistance,and increased cycling efficiency. 
The design increases bike derailleur shifting speed, causes no noice when shifting speed and prevents bike chain falling. 
 
Note:
Please choose the same size as original guide wheel, if not the same, you can choose smaller size than the original wheel but not the larger one. 
 
Package includes:
1 x Bicycle Positive and Negative Teeth Guide Wheel;