The Hirose DF40HC(3.0)-80DS-0.4V(58) is an 80-position receptacle from the DF40 series, designed as the board-side half of a board-to-board mezzanine interconnect. With a 0.016" (0.40mm) pitch and a mated stacking height of 3mm, it mates with the matching DF40 header to create a compact, parallel board stack. The gold-plated center strip contacts and dual-row layout suit high-density signal routing inside portable electronics, handheld devices, and other space-constrained assemblies where board spacing is tight.
The critical mechanical parameter here is the mated stacking height of 3mm, paired with a height above board of 0.114" (2.90mm) for the receptacle alone. That 3mm gap between PCBs is the z-axis clearance your enclosure and component keep-out zones must accommodate. The 0.40mm pitch means trace routing between pads is tight — expect micro-via fanouts or dogbone escape patterns in the breakout region, especially for the inner rows.
The ROHS3 compliance covers the full substance restriction list for EU-market equipment, which clears a regulatory gate for most commercial and consumer designs.