The Shimano Tiagra RD-4700 Rear Derailleur. FEATURES: Revised cable pitch offers accurate and long-lasting performance Compatible with up to 34t cassette Wide link design increases rigidity 11 tooth pulleys for reduced pulley wear and chain noise Compatible only with ST-4700 and ST-4703 shifters SPECS: Cage Length: Medium (GS) Drivetrain Speeds: 10 Largest Cog: 34T (Medium Cage) Rear Der/Shifter Compatibility: Shimano Road