What this connector is
The Amphenol FCI 87901-426HLF is a dual-row, 0.100 inch (2.54 mm) pitch unshrouded male pin header in the BERGSTIK II series — a long-running board-to-board interconnect family. It mounts through-hole and carries 26 square pins on 0.100 inch row spacing, with both the mating face and the solder tail finished in 100 µin (2.54 µm) tin. Rated 5 A per contact at 110 V, the housing is black Nylon with a UL94 V-0 flammability rating.
Key ratings for the BOM decision
At 26 positions this is the largest dual-row member of the BERGSTIK II range at the 0.100 inch (2.54 mm) pitch — the pitch and dual-row format confirm the standard 2.54 mm through-hole footprint a designer would route to. The 5 A per circuit rating handles both power and signal rails at board-to-board stack heights; the tin plating grade is appropriate for non-frequent mating (the push-pull fastening type implies seated-and-fixed pairing rather than repeated reconnection cycles). The 0.100 inch (2.54 mm) insulation height is the mated stack height reference — important when checking the z-height budget between daughtercard and backplane or midplane. All 26 positions are fully loaded, so no partially-stocked insertion to account for.
What it connects
As a board-to-board header it mates with the matching BERGSTIK II dual-row receptacle housing or IDC-style female connector. The square pin cross-section and push-pull fastening type indicate this is intended as a fixed-stack partner — not a latching cable plug. The unshrouded header leaves pinout flexibility on the layout side but requires mechanical alignment features elsewhere in the stack to prevent canting during mating.