The Hirose DF12(3.0)-30DP-0.5V(86) is a 30-position header with outer shroud contacts from the DF12 series, designed for board-to-board mezzanine stacking at a 3mm mated height.
The 3mm mated stacking height sets the z-axis gap between the two boards; this is fixed by the connector body, not adjustable. 30 positions in two rows means a 15-per-row layout, so the footprint is roughly 7.5mm long plus the alignment features. Surface-mount termination with gold-over-nickel contacts (8.00µin gold) is standard for moderate-cycle internal connections — the gold thickness is adequate for the expected mating life in a one-time-assemble or occasional-service scenario.
Termination is surface-mount only — no through-hole option. For a harness builder: there are no crimp terminals here; this is a pure SMT board-to-board interconnect.