SP PV-8 Road Bike Dynamo Hub (Rim V-Brake, 3.0 Watts, available for 32H/28H/24H/20H) - Lightest and Most Efficient on the Market The Most Efficient Dynohub on the Market - incomparable 72% efficiency when light are on tested under the most rigorous StVZO "Golden Standard" specification set One of the Lightest Dynohubs available at only 390 g (13.75 ounces) Designed specifically for road bike 700c wheels and virtually drag-free Output: 6V2.4W for 700c wheels; quick release axle, 100 mm O.L.D 2-year Warranty. Package includes: Hub x1, Plug Converter Set x1