Board Footprint and Orientation
The 3-644754-5: The 0.175" (4.45 mm) post length is the solder tail dimension that determines the plated-through-hole depth.
Mating Retention and Vibration Resistance
It is not a screw-lock or secondary latch, but it prevents the pair from walking apart under moderate vibration — enough for an industrial cabinet or general-purpose equipment that sees occasional movement.
Electrical and Thermal Envelope
Rated 600 VAC — the voltage ceiling for line-to-line or line-to-ground in equipment with basic insulation.