0.40 mm pitch, 1.14 mm stack — the DF40T mezzanine plug for tight board spacing
The Hirose DF40TC-50DP-0.4V(58) is a 50-position, dual-row plug from the DF40T series of board-to-board mezzanine connectors. It operates at a 0.016" (0.40 mm) pitch and mates to a 1.14 mm stack height, making it suited for parallel PCB stacking in space-constrained handheld and portable electronics.
Gold flash and the real duty limit
For applications requiring frequent board separation, a thicker gold grade in the DF40 series would be the correct call. The solder retention feature on the SMT feet adds shear resistance during reflow and handles the strain from the mating receptacle's normal force.