DF40C-70DS-0.4V(51) from Hirose Electric Co Ltd is a fine-pitch rectangular receptacle connector designed for compact, high-density board-to-board interconnect applications. With 70 positions, 0.40 mm pitch, dual-row SMT mounting, and a low 1.5 mm mated stacking height, it is well suited for slim portable electronics, industrial control modules, embedded computing platforms, display assemblies, and other space-constrained designs where signal density and profile matter. Engineers typically select this series when they need reliable interconnection in compact layouts without sacrificing assembly compatibility for reel-based automated production. The supplied status indicates Active, which is favorable for ongoing production use, although lifecycle verification from Hirose or current channel data is still recommended because the separate lifecycle field is listed as unknown. RoHS compliance information is not explicitly provided in the supplied specifications, so compliance should be treated as information not available until confirmed through the manufacturer datasheet or formal compliance documentation.