Shimano Ultegra FD-R8150 Di2 Front Derailleur - 2x12-Speed Braze-on Down Swing For 50-54t Max BLK/SilverShimano Ultegra FD R8150 Di2 Front Derailleur 2x12 Speed Braze on Down Swing For 50 54t Max Black Silver. Combining Shimanos Di2 platform and the road incarnation of Hyperglide+ the Ultegra FD R8150 front derailleur shifts between chainrings with the fast and seamless action. Small sleek and lightweight front derailleur Frontal area is smaller than previous designs to reduce aerodynamic drag Top gear teeth capacity: 50 54t TECH SPECS Double or Triple