M21 rear derailleurs are designed to work with 6- and 7-speed Shimano road and mountain shifters. Enjoy the wide variety of bikes you can get up and running with M21 rear derailleurs.

• Robust composite and steel construction
• Compatible with Shimano 6- and 7-speed mountain and road systems
• 21t chain wrap capacity
• Color: Black
• Largest Cog: 30
• Rear Derailleur Mount Type: Dropout Claw Hanger
• Chain Wrap Capacity (teeth): 21
• Cage Length: Short
• Rear Der/Shifter Compatibility: Shimano Mountain
• Drivetrain Speeds: 6, 7