Rated at 5 A per contact with gold or gold GXT™ plating at 15.0µin (0.38µm) on the mating surface, this is a general-purpose board-to-board interconnect suited for signal and moderate power duty on a through-hole PCB.
The 0.100" pitch is the bread-and-butter spacing for prototype boards and standard perfboard — you can route a trace between pads without squeezing, and the 0.318" (8.08mm) mating length gives enough wipe for reliable contact with a standard female socket.
Through-hole mounting and unshrouded design
This is a through-hole header — the 0.120" (3.05mm) solder post length suits standard 0.062" to 0.093" PCBs.
The 68001-236HLF is the closest functional peer — same 36 positions, same 0.100" pitch, same unshrouded single-row layout, same gold GXT plating at 15.0µin. The difference is the overall length: the 78511-236HLF has a 0.538" (13.67mm) overall contact length versus 0.450" (11.43mm) for the 68001-236HLF. That extra length comes from a longer mating pin (0.318" vs 0.230"), which gives more wipe depth for thicker board stacks or deeper receptacles. If your mating socket has a standard insertion depth, either works — but the 78511 gives you more margin on the wipe.