The Amphenol FCI 79821-406HLF is a dual-row unshrouded male header in the BERGSTIK II series, configured for board-to-board stacking at 0.100 inch (2.54 mm) pitch. It carries 6 positions across two rows, with tin-plated phosphor bronze contacts rated 5 A per circuit at 110 V and UL94 V-0 black insulation. The push-pull push-pull fastening and square contact shape make it a common low-profile interboard jumper and signal bus header in industrial automation applications where a reliable, through-hole mate is required rather than a sealed or locking connector.
What the ratings mean for fit
At 0.100 inch pitch and 6 positions in a dual-row layout, this is the standard 2.54 mm grid that matches the majority of breadboard and proto-board footprints — routing density is modest, so signal integrity is not a concern for the pitch itself. The 5 A per-circuit rating at 110 V is a genuine power-capable header, not a signal-only part: individual circuits comfortably carry low-level power or gate-drive lines without derating to room-temperature limits. Tin plating at 100.0 µin (2.54 µm) thickness on both the mating face and the post gives solid wipe and solderability but no reconnection-cycle premium — the series is aimed at permanent or semi-permanent board stacks rather than field-service mate cycles. The 0.200 inch (5.08 mm) post length gives adequate stand-off for through-hole reflow or hand-soldering; the 0.430 inch (10.92 mm) mating length is long enough to maintain engagement through light stack misalignment. All 6 positions are loaded — no open sites — so the full dual-row footprint is present on the board. The insulation height of 0.100 inch (2.54 mm) matches the row pitch, which means the board-to-board stack height is governed entirely by the PCB thickness and any connector body above it.