The all-new Shimano Deore XT M8100 series of derailleurs brings a new level of drivetrain silence thanks to decreased tension in the low gear position and an added bumper on the pulley cage. Larger 13T pulleys increase efficiency and chain management while compatibility with SHIMANO's new 12-speed cassettes boosts range. Details: CAGE LENGTH SGS/Long MAX FRONT DIFFERENCE 0 COLOR SERIES COLOR MOUNT Direct attachment (conventional)/Direct mount compatible TENSION PULLEY BEARING Sealed Bearing GUIDE PULLEY BEARING Sealed Bearing NUMBER OF PULLEY TEETH 13 SERIES XT GENERATION M8100 MAX LOW SPROCKET 51t MIN LOW SPROCKET 45t TOP NORMAL SPRING TYPE Shimano Shadow RD+ REAR SPEEDS 12 WEIGHT 284 grams