Shimano Altus RD-M310 Rear Derailleur - 7, 8 Speed, Long Cage, Black

 The Shimano RDM310-Smart rear derailleur has a Wide Link design for increased rigidity and precise shifting.

• Oversized 15-tooth tensioner and 13-tooth guide pulleys reduce noise and wear
• SMART CAGE pulley plate provides more ground clearance
• Advanced light action with precise shifting
• Compatible with Shimano HG 6/7/8 speed chains
• 7/8-Speed
• 13t upper and 15t lower pulleys