Deore XT Shadow Dyna-Sys 10-speed rear derailleur delivers reliable & precise shifting with a stiff & lightweight open design Shadow features a super low profile design that reduces the risk of damage from trail side hazards Single tension spring prevents contact with the chainstay resulting in a silent ride Direct cable routing prevents snagging from any trail side hazards All-alloy construction leads to lower weight without compromising strength & durability Four fluorine-coated link pin bushings make this one of the slickest shifting derailleurs on the trails High rigidity wide outer link braces the pulley body to increase pivot joint rigidity resulting in a crisp shift Strong return spring for a positive shifting feel Improved cable pull ratio provides a more accurate shift action making the system less prone to contamination & trail chatter Dyna-Sys 10-speed compatible only Durable sealed bearing pulleys 35T capacity GS cage Top normal springuses the spring to select higher gears Weight 230 grams