The 4-103330-0-28: This 56-position header from the AMPMODU Mod II series is a breakaway design, meaning the pin strip can be snapped to a shorter length if the full 56 circuits aren't needed — a practical option for prototype runs or BOM flexibility where the board layout has unused positions.
The 0.230" (5.84mm) mating pin length and 0.120" (3.05mm) solder tail length are standard for through-hole solder termination; the square pin shape (0.025" square typical for the series) provides a reliable gas-tight joint when soldered.