The 77313-162-40LF: The unshrouded breakaway style means you can snap the header to a shorter length if your BOM calls for fewer than 40 positions, though the base part ships as a full 40-position strip. The through-hole tails are tin-plated (78.7 µinch / 2.00 µm) and solder easily with wave or hand-solder processes.
Contact Interface and Mating Cycles
The mating contact finish is 30.0 µinch (0.76 µm) gold over nickel — a thickness that supports repeated mating without exposing the base metal. The male pins are square phosphor bronze, a standard spring material that holds its shape under repeated insertion.