100-Position Mezzanine Header at 0.80 mm Pitch
The Hirose FX6-100P-0.8SV2(71) is a 100-position, dual-row surface-mount header from the FX6 series, designed for board-to-board mezzanine stacking. It uses a 0.031" (0.80mm) pitch, which keeps the board footprint compact while still allowing reasonable routing density for a 100-signal interconnect. The connector type is listed as Header, Outer Shroud Contacts — meaning the male pins are positioned along the outer edges of the insulating shroud, and they mate with the center strip contacts on the matching FX6 receptacle. This header carries gold-plated contacts, which is the right call for a mezzanine application where the boards may be mated and unmated during test or rework, as gold resists corrosion and maintains consistent contact resistance over repeated cycles.
The header itself stands 0.275" (6.99mm) above the board surface, but the mated stack height depends on the receptacle half. The spec lists mated stacking heights of 7mm and 9mm, which means you pair this header with either the standard-height FX6 receptacle or a taller version to get the board-to-board gap your enclosure needs. For comparison, the sibling FX6-100P-0.8SV(71) is shorter at 0.197" (5.00mm) above board, giving a different mated stack height. If your design calls for a specific z-height, pick the header height that gets you there with the matching receptacle.
Position Count and BOM Fit
With 100 positions across two rows, this header matches a 100-circuit BOM line. The FX6 series also offers an 80-position variant (FX6-80P-0.8SV(71)) at the same 0.80 mm pitch, so if your signal count is lower, that's a direct pitch-compatible drop-in for a smaller footprint. The 100-position version is the full-density option for this series, giving you the maximum I/O count in the same connector format.