Race Face Aeffect R E-Bike Bosch Gen 4/5 Cranks Extra Burly E-bikes are great for riders who want to experience the joys of mountain riding and want a little extra boost when climbing or riding longer distances. With increased e MTB torque comes stronger components that won't let you down. The Race Face Aeffect R E-Bike Gen 4/5 Cranks bring the burly, purpose-driven design of Aeffect R to light-assist and full-power e-bikes. While they are designed for rowdy, power-down riding, the 485g weight puts them among the lightest alloy e MTB cranks on the market. These are optimized for use with Bosch Gen 4 Performance Line CX drive systems and are compatible, but not optimized, for use with Bosch Gen 2 drive systems. Features7050 aluminum construction that is lightweight and highly durable Optimized for use with Bosch Gen 4 Performance Line CX drive systems Compatible for use with Bosch Gen 2 drive systems (but not optimized for)SPECIFICATIONSSpeeds11, 12BB Compatibility ISISChain Ring Direct Mount Crank Arm Length160, 165, 170mm BB Spindle Interface ISISChainring Material-Bolt Center Diameter (BCD)Direct Mount Crank Arm Material7050 Aluminum Chainline-Bottom Bracket Included No Intended Usee MTBWeight485g | Race Face | Aeffect R E-Bike Bosch Gen 4/5 Cranks 160Mm, Bosch Gen 4 / Gen 5 | Aluminum