For bikes that use a freewheel instead of a cassette, the microSHIFT M26C is specifically designed to accommodate the 13t gear commonly found at the small end of a freewheel range. Shifting will be much improved with this model compared to a conventional derailleur not designed for freewheel use. Robust composite and steel construction Compatible with Shimano 7- and 8-speed mountain and road freewheel systems