It uses a 0.100" (2.54mm) pitch and through-hole solder termination, making it a standard board-to-board interconnect for prototyping, break-out boards, and internal wiring harnesses where a shrouded keying feature isn't required. The 30.0 µ" gold plating on the mating surface handles repeated connect-disconnect cycles better than a tin-finish equivalent, while the UL94 V-0 rated black housing meets the flammability requirement for equipment inside an enclosure.
The 91276-107HLF is an unshrouded header, so it does not have a plastic shroud around the pins. If your application needs polarization or pin protection during mating, you would look at a shrouded BergStik header — but those are a different product family with a different footprint.