The Hirose DF30FC-20DS-0.4V(81) is a 20-position receptacle from the DF30 series, designed for tight board-to-board stacking. The 0.016" (0.40mm) pitch and 0.9mm mated stacking height mean it fits into ultra-slim portable electronics — phones, wearables, or compact modules where every tenth of a millimeter of z-height matters.
Sizing It Against the 24-Position Sibling
The DF30FC-24DS-0.4V(81) shares the same 0.016" (0.40mm) pitch and 0.9mm stack height but carries 24 positions instead of 20. If your BOM calls for 20 circuits, the 24-position part won't fit the footprint — the extra four contacts shift the overall length. Stick with the 20-position for a direct board layout match.