4 characteristics for 3-Athlete:
- exceptional dropouts
- lugs with cut-outs
- unusual BB cover (without recesses)
- "own design" of the inscription Eddy Merckx (early series)
You will find all these features in this frame
All the early Pro 753 I have seen so far had:
- the classic Campagnolo dropouts
- normal short lugs
- BB cover with recesses (4 or 6)
- the "own design" of the inscription Eddy Merckx (mostly)
- the early series for the American market had the numbers ~Z1100 and red and white painting (identical to Team TeVe Blad 1985)