The ultimate in reliable lightweight mono lever shifters from the ultimate Shimano MTB groupset, XTR shifters are engineered to perform in the most demanding conditions Light to the touch but positive and crisp Instant Release for super fast shifts, delivering the chain to the next gear the moment the lever is actuated with no hesitation Mono lever allows the shift lever to perform both up and down shift functions when pushing with thumb Shifter features a precision indexing drum with four sets of ball bearings providing low-friction smooth shifting Long carbon shift levers with rubber inserts help to lower shifting effort and improve grip Composite barrel adjuster Band on mount For use with 12-speed only Weight: 79 grams