0.50mm Pitch Mezzanine Header, 50 Positions, 3.5mm Stack Height
The Hirose DF12B(3.5)-50DP-0.5V(86) is a 50-position, dual-row header from the DF12 series, designed for board-to-board mezzanine stacking at a fixed 3.5mm mated height. The 0.020" (0.50mm) pitch packs 50 circuits into a compact footprint — the tight pitch means the PCB routing needs to fan out from the connector body, so plan your escape traces before committing the layout. Outer shroud contacts with gold plating (8.00µin) on the mating interface handle signal-level current; the gold flash is adequate for the typical few mating cycles in a production assembly but won't hold up to repeated field disconnect.
If you're designing a new board, the DF12 series still offers active 0.50mm pitch mezzanine headers at the same 3.5mm stack height — check the current product line for a live order code that matches your position count.
What Crosses Into the Harness You've Got
Mates with the matching DF12 series receptacle (the female side of the mezzanine pair) at the same 3.5mm stack height. The header is surface-mount only — no through-hole variant in this form factor. The solder retention tabs mean the footprint includes extra pads beyond the signal pins; confirm the PCB land pattern matches the Hirose recommended layout before ordering a reel. If you're re-pinning an existing assembly on site, you're not — this is a reflow-soldered header, not a field-repairable crimp connector. The whole board stack gets replaced.