DF40C-24DP-0.4V(51) from Hirose Electric Co Ltd is a fine-pitch rectangular board-to-board connector designed for compact electronic assemblies where space, stacking flexibility, and reliable contact performance matter. With a 0.40 mm pitch, 24 positions, dual-row layout, and SMT mounting, it fits high-density designs such as mobile devices, industrial handheld equipment, embedded control boards, and compact communication modules. Engineers often select this series for low-profile interconnect requirements, multiple mated stacking height options, and gold-plated contacts that support stable signal transfer in tightly packaged systems. Based on the provided product data, the part status is Active, which supports ongoing design consideration, although lifecycle confirmation should still be checked against current manufacturer documentation. RoHS compliance information is not explicitly provided in the supplied specifications, so compliance status should be treated as information not available until verified through the official datasheet, manufacturer declaration, or authorized distribution source.