Shimano Dura-Ace FD-R9250 Di2 Front Derailleur - 2x12-Speed Braze-on Down Swing For 50-55t Max BLK/SilverShimano Dura Ace FD R9250 Di2 Front Derailleur 2x12 Speed Braze on Down Swing For 50 55t Max Black Silver. Despite its smaller lighter design the Shimano Dura Ace FD R9250 offers ultra fast front shifting. Fast Di2 shifting performance Smaller sleeker lighter Frontal area is smaller than previous designs to reduce aerodynamic drag Top gear teeth capacity: 50 55t TECH SPECS Double or Triple Double Drivetrain Speeds 12 Derailleur Capacity 16 Front