The Shimano XTR M9100 Crank Arm Set is the secret behind the power of your favorite mountain bike. The XTR groupset is one of the best performing trail groups on the market and provides excellent pedaling performance at the back of this crankset. The arms of the crank are made of forged alloy with Hollowtech technology which helps balance the low weight you need for speed along with the durability that is required on difficult trail rides. It utilizes special gear teeth that are made specifically for mountain riding. Please note that this product includes just the arms and does not include a bottom bracket or chainring. If you are ready for smooth riding over the most difficult terrain, the Shimano XTR M9100-1 Crankset.