Offering pro-level features, the 10-speed compatible Tiagra rear derailleur gives high performance at a low price Wide link design increases rigidity & service life Advanced light action for low-friction shifting up or down the block Alloy body's & outer link leads to lower weight without compromising strength & durability 11-tooth pulleys for reduced pulley wear & chain noise Two fluorine-coated link pin bushings for low-friction performance 32 tooth max with triple, 34 tooth max with double chainset Compatible with 10-speed road drive systems