Wide link Shadow design Dyna-Sys 10-speed top normal Deore rear derailleur Double servo-panta mechanism for smooth light action shifting Single tension spring prevents contact with the chainstay resulting in a silent ride Alloy & steel construction leads to lower weight without compromising strength & durability Wide link design increases rigidity & service life Top normal return spring lends to incredibly intuitive operation when combined with Rapidfire shifters Large 11 tooth pulleys are used for longer life Two fluorine-coated link bushings for low-friction operation Dyna-Sys 10-speed compatible only 45T capacity SGS cage Compatible with 32-36T low sprocket