Shifting performance is important when you're riding in demanding terrain. Being able to go from a high gear to a low gear quickly will save your legs on those tough climbs. The Shimano Deore RD-M4120 10/11-Speed Rear Derailleur has a versatile design for both 10 and 11-speed drivetrains. It features Shadow technology for more stability during aggressive riding. This derailleur has a maximum cog size of 42T.

• Versatile design for both 10 and 11-speed drivetrains
• Shadow technology for better derailleur stability during aggressive riding
• Maximum cog size: 42T