Thinkrider Smart Bike Trainer Built-in Power Meter MTB Road Bicycle  Bike Trainers Platform Indoor Cycling Platform

    Notice before buying:The Cassette is for demonstration purposes only, not including the product, you need to purchase it separately.it can fit 8-11 speed cassette.

NOTE:

         1.if you use the SRAM SX/NX 12 speed cassette,don't need change the free hub,you can direct use it,

        2.if you need use the sram GX 12 speed cassette,need change the 12 speed XD free hub

        3.if you want use other model 12 speed cassette,need change to 12 speed the free hub