Shimano Dura-ace Di2 7970 Braze-on Front Derailleur

This is an electronic, digital intelligence, 10 speed, front derailleur, that gives staggering reductions in the effort and time taken for front shifts, compared to the Dura-Ace mechanical system.
It has a high tolerance, cold forged aluminium and composite construction, with a programmed automatic motion, that operates smoothly at the touch of a switch, ensuring unmatched drivetrain efficiency.
The system replaces the mechanical cable with electrical wires, removing the poor shifting performance caused by contaminates, corrosion and cable stretching.
The front derailleur also trims automatically, in response to the position of the rear derailleur on the cassette, to ensure no chain rub and a quiet unobtrusive ride.
This is a Braze-on fit, but a Band-on adaptor is also available.