That's 4 and 5, both 3 and 4 have external headsets.
I think the main difference is that the CAAD3 had straight seatstays whereas the CAAD4 had the signature CAAD S bend ones
@PhilDAS started
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That's 4 and 5, both 3 and 4 have external headsets.
I think the main difference is that the CAAD3 had straight seatstays whereas the CAAD4 had the signature CAAD S bend ones