The Ultegra Di2 model comes with ENVE 45 Foundation wheels wrapped with its own SES tyres in a 29mm width. ENVE also supplies a proprietary carbon aero post, aero stem, SES Aero handlebar, and even an ENVE-edition Selle Italia Boost saddle.
The premium Dura-Ace Di2 bike steps up the wheel package to the latest SES 4.5 wheelset, with a carbon-railed version of the Boost saddle.