DF40C-12DP-0.4V(58) from Hirose Electric Co Ltd is a compact rectangular board-to-board mezzanine connector designed for high-density interconnect applications where space, profile, and mechanical stability matter. As part of the DF40 series, it offers a fine 0.40 mm pitch, 12 positions, dual-row layout, SMT mounting, gold-finished contacts, and solder retention features that support reliable assembly in compact electronics. Typical use cases include portable devices, embedded control boards, communication modules, industrial miniaturized assemblies, and other designs requiring low-profile board stacking. With multiple supported mated stacking heights in the DF40 family, it fits designs that need flexible vertical spacing. Lifecycle status for this specific part is listed as unknown, so engineers should confirm current manufacturer status before committing to long-term production. Formal RoHS compliance information is not provided in the supplied specifications, therefore compliance should be treated as information not available until verified through official Hirose documentation or manufacturer-backed declarations.