THE NEW GENERATION OF XT Shimano has been making some of the best bicycle components since the 1970s and they continue to produce some of the most sought-after components in the industry. XT is Shimano's work-horse mountain bike group features some of the finest technology and produces an incredibly clean and reliable shift. The newest generation of XT is not only new and shiny, it comes with all-new technology. The Shimano XT RD-M8100 Rear Derailleur has been upgraded from 11-speed to 12-speed and has the capacity to go up to a 51 tooth cog on the rear. The RD-M8100 is designed for 1x12 drivetrains and comes with the SGS long cage. MODEL NO