D-Fly (the exact name is SM-EWW01) is the name of the brand new magic box that wirelessly transmits information from the Di2 system - the electronic shifting system from Shimano - to compatible Velocompis. D-Fly is compatible with Dura-Ace 9070, Ultegra Di2 and Ultegra 687076770 E-Tube systems. Simply connect the D-Fly to an E-Tube connector and the Di2-equipped bike seamlessly connects to a compatible wireless bike computer.

The D-Fly transmitter transmits data using a proprietary ANT wireless protocol and can show the rider the gear engaged, battery life, and likely cadence, deployment or other data.

For its launch, the D-Fly will initially be operated with the Pro Scio ANT + bike computer; Pro is the component and accessory offshoot of Shimano. However, Shimano is thinking outside the box and is planning compatibility with the navigation system manufacturer MIO and other cycling computers for the 1st quarter of 2014. Shimano's own PRO Scio ANT + bike computer weighs 80 grams and has been available in white or black since January 2014.

The Di2 wireless module SM-EWW01 - or D-Fly for short - is just 38 millimetres long, 25 millimetres wide and 12.5 millimetres high and weighs less than 5 grams. The wireless module uses the power from the battery of the Di2 shifting unit. The small dimensions offer a wide range of mounting options on the bike.