It uses a 0.100" (2.54mm) pitch on both the row spacing and the pin-to-pin spacing, which is the standard footprint for legacy board-to-board interconnects. The through-hole solder termination and 0.120" (3.05mm) post length suit it for standard PCB thicknesses around 1.6 mm; the 0.190" (4.83mm) mating contact length provides a solid wipe for a reliable connection.
Rated 5 A per circuit at 110 V, the 79425-440HLF is a signal-level header — the 5 A per pin is typical for logic-level power and low-current I/O, not bus-level distribution. The 110 V rating gives enough headroom for 48 V telecom rails and 24 V industrial supplies without creepage concerns at this pitch. The tin-plated mating contacts (100.0 µin / 2.54 µm thick) are cost-effective for moderate mating-cycle applications — expect a few hundred cycles before the tin wears through.