Ultegra FD-R8150 12spd.Combining SHIMANO's new DI2 platform and the road incarnation of Hyperglide+, the Ultegra R8150 front derailleur shifts between chainrings with the fastest, most seamless action on the market. Features: Fastest ever front shifting, 45% faster than FD R9150. Smaller, sleeker, lighter. Frontal area reduced by 33%. Weight cut to 116 g. Top gear teeth capacity: 50 54T.