microSHIFT ADVENT E-Series Cassette - 9 Speed 11-42t Black ED CoatedmicroSHIFT ADVENT E Series Cassette 9 Speed 11 42t Black ED Coated. The microSHIFT ADVENT E Series cassette is designed for the rigors of E bikes. This cassette utilizes a harder material on the small cogs to reduce wear and extend the life of the cassette and chain. ED coated steel cogs are specifically designed to withstand the added force of eBikes 11t cog is constructed with hardened chromoly steel to provide durability and extended life Includes