Since there's no derailleur cable loop visible (or any derailleur cables for that matter), and the cranks are Dura-Ace, I think it's a fairly safe bet that it's Di2.
@Regal started
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Since there's no derailleur cable loop visible (or any derailleur cables for that matter), and the cranks are Dura-Ace, I think it's a fairly safe bet that it's Di2.