Shimano's GRX components are all tailor-made for gravel riding performance, and the RX750 wheelset is no exception. Balancing weight and durability, this 650b wheelset delivers the stiffness and control we need when riding over mixed terrain, from dirt to gravel to the ribbon of singletrack. Like Shimano's other tried and true wheel offerings, the RX750 also uses an easily serviceable cup and cone bearing system within the steel hub body. The heavier steel at the hub is no penalty for rotational weight and helps extend the durability of the wheelset. The aluminum rim keeps weight in check and is shaped for optimal mud-shedding to help us get through that infamous Oklahoma peanut butter.