Pin geometry and board fit
The 75401-001LF: The 0.025" (0.64 mm) square pin above and below the flange sets the PCB hole diameter at 0.032"–0.034" (0.81 mm–0.86 mm) — a standard press-in fit for a soldered through-hole pin. The overall length of 0.345" (8.76 mm) gives enough protrusion for wire-wrap or a mating socket on the top side while leaving the solder tail through the board. Board thickness range is 0.062" to 0.125" (1.57 mm to 3.18 mm), covering the most common PCB stack-ups from thin signal boards to thicker power-distribution planes.
Contact finish and material
Phosphor bronze gives good spring retention in the pin retention feature.