Yes i thought all that, was looking at the Ultegra groups on Shimano site and assumed that they just used the 6400 seatpost for the 6500/6600 group, but then i saw this
https://www.ebay.com/itm/234309719233?hash=item368df294c1:g:7yoAAOSwNpFhpGhX
@1561 started
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Yes i thought all that, was looking at the Ultegra groups on Shimano site and assumed that they just used the 6400 seatpost for the 6500/6600 group, but then i saw this
https://www.ebay.com/itm/234309719233?hash=item368df294c1:g:7yoAAOSwNpFhpGhX