For bikes that use a freewheel instead of a cassette, the microSHIFT M26C is specifically designed to accommodate the 13t cog that is commonly found on the small end of a freewheels' range. Shifting will be much improved with this model versus a conventional derailleur not designed for use with a freewheel. FEATURES: Robust composite and steel construction Compatible with Shimano 7- and 8-speed mountain and road freewheel systems SPECS: Color: Black Largest Cog: 34 Rear Derailleur Mount Type: 10x1 Standard Chain Wrap Capacity (teeth): 45 Rear Der/Shifter Compatibility: Shimano Mountain Cage Length: Long Drivetrain Speeds: 8 , 7