Breakaway Cycles - How about a throwback. When's the last time you saw a still fully functional Shimano flight deck computer? I guess you could call it the precursor to Di2 with
Shimano Flight Deck SC-6502 Computer Head 8-10sp - $89.99
Shimano Drop Bar SORA Flight Deck 3x9 Shifter Set ST-3304 | eBay
How to Thoroughly Destroy a Shimano 105 STI 5600 Flight Deck Left Shifter - Instructables
Shimano Ultegra 6600 ST-6600 10 Speed Shifter Pair+Full Flight Deck Co – EJRecyclery - Cycling New & Used
Shimano Flight Deck SC-6502
Help with shimano sc-6502 flight deck for ultegra 6600 - Only notices changes on the front derailleur but not from the rear one rendering the rpm function useless : r/bikewrench