1. AEST 21 Speed Rear Derailleur Pulley for Shimano
2. Weight:9g
3. Material:AL7075 CNC Machined
4. Diameter:Ø5 or 6mm 
5. 11T for Shimano&sram 7/8/9 se.Bear 1PC
6. Color:Anodized Red/Gold/Ti/blue/Black