40-Position Mezzanine Header at 0.50 mm Pitch
The Hirose DF12(4.0)40DP0.5V(80 is a 40-position header from the DF12 series, designed for board-to-board mezzanine stacking. The mated stack height is 4 mm, which sets the spacing between the two PCBs.
Obsolete — Sourced Through Surplus Channel
No new factory orders — the only supply is through the surplus and broker market. There is no listed official successor from Hirose, so a direct pin-compatible drop-in is not on record.
What the 4 mm Stack Height Means for Board Layout
The 4 mm mated stack height is the dimension from the top of the bottom board to the bottom of the top board when the pair is mated.