The DF37C-24DP-0.4V(51): At a 0.016" (0.40mm) pitch, this connector packs 24 circuits into a dual-row layout that keeps the footprint small. The outer shroud contacts are plated with 2.00µin (0.051µm) gold — a flash finish suited for the limited mating cycles typical of a stacked PCB assembly, not repeated field disconnect. The header sits 0.030" (0.75mm) above the board, and when mated with the matching DF37 receptacle, the stack height comes to 0.98mm. That z-budget is the whole point: it lets you sandwich two boards at just under a millimetre apart, which is common in compact handheld or module-on-motherboard designs.
The mated stack height of 0.98mm is the dimension that decides whether this connector fits your mezzanine gap. With the header standing 0.75mm above the board surface, the mating receptacle contributes the remaining height to reach that 0.98mm total. If your board-to-board clearance is tighter or looser than that, the DF37 series includes other variants — but for a 0.98mm stack, this is the header half you need.
Surface-mount termination, dual-row layout. The 0.40mm pitch demands a precise solder paste stencil and a reflow profile matched to the small pads. The outer shroud contacts are the mating interface — they wrap around the receptacle's contacts on the opposite board. No through-hole posts, no press-fit; this is a reflow-only part.