Generate your own electricity when riding – no need for batteries Compact and light-weight 20” Kinetix Comp wheel set Compatible with the BioLogic ReeCharge There’s nothing we like better than clean energy. The Joule II dynamo hub 20” wheel set has a built-in generator that produces electricity when the hub rotates while riding. Designed to fit 74 mm forks, this wheel set features one of the smallest, lightest dynamo hubs on the market. Rated at 6V/2.4W at 15 km/hr (9.3 mph) under 15 ohm load.