Shimano M4100 Deore 10 Speed Rear ShifterThis rear shifter is engineered for fast and fun MTB riding, as it delivers smooth and dependable shifting operation as you shred the trails. It features a 2-way release, which allows shifting from various riding positions. This means that its upper lever still performs the same shift function, but it can now also swing in either direction, allowing it to be released by your thumb or your index finger.Features: Use: MTB Speed: 10 speed Release: 2-way release Adjustment: Barrel adjuster Optical Display: Options with or without available Mount: Band-on or I-spec-EV options available separately Includes: Optislick inner and SP41 outer cables Single or Pair: Single Position: RearTechnologies: 2-way Release: 2-way release allows shifting from various riding positions; the upper lever still performs the same shift function, but it can now swing in either direction allowing it to be released by the thumb or index finger. Vivid Indexing: Light to the touch but positive and crisp, Vivid indexing provides a constant amount of shift lever force across all 10 sprockets. Dyna-Sys 10-speed Compatible: For use with precision 10 speed MTB drivetrains.A 2-year warranty is offered with all Shimano products from Chain Reaction Cycles (3 years on Dura-Ace and XTR products).Buy Shimano Components from Chain Reaction Cycles, the World's Largest Online Bike Store.