Unlock the versatility of wide-range 11-speed gearing with the Shimano Deore RD-M5100 11 Speed Rear Derailleur. Designed to pair with the Deore CS-M5100 11-51t cassette, this derailleur has a huge capacity which enables it to smoothly shift in and out of that monster 51t cog. Shimano's Shadow Plus design creates a low-profile to help prevent damage from rocks and trail debris. Chain stabilising technology makes for a quiet drivetrain in all gear positions and reduces chain drop, slap and noise. Larger 13t pulleys allow for smooth operation, and reduced spring and chain tension in the low gears will reduce wear and tear and strain on the components.