The Shimano Acera RD-M3020 rear derailleur features Double Servo technology to provide smooth, precise shifting and helps you ride challenging terrain with fewer interruptions

• Double Servo mechanism enables the rear derailleur to move in an optimum path
  
• Versatile performance and wide compatibility
  
• SGS Long cage
  
• Rear Derailleur Mount Type: 10x1 Standard
  
• Chain Wrap Capacity (teeth): 45
  
• Rear Der/Shifter Compatibility: Shimano Mountain
  
• Cage Length: Long
  
• Drivetrain Speeds: 7/8
  
• Color: Black