The 7-146256-0: This is a 40-position, dual-row unshrouded breakaway header from the AMPMODU Mod II series, on the standard 0.100" (2.54mm) pitch that matches legacy wire-wrapping and prototyping grids. The through-hole solder tails are 0.120" (3.05mm) long, and the mating pin length is 0.230" (5.84mm) — a common length for IDC ribbon-cable receptacles or individual crimp sockets.
Gold mating finish vs tin post — the real durability difference
The mating interface is gold over 15.0µin (0.38µm) thickness, while the solder tails are tin-plated at 100.0µin (2.54µm). The tin post is standard for soldering; the thickness is generous enough to wet well through wave or hand solder.
The lifecycle status is Active. RoHS compliant.
Peer check: 1376779-2 as a functional second-source
The closest alternate in the same series is 1376779-2: same 40-position dual-row layout, same 0.100" pitch, same 3 A rating, same UL94 V-0 LCP housing. The difference is the gold plating thickness on the mating surface — 8.00µin (0.203µm) vs the 15.0µin on 7-146256-0. For low-cycle or cost-sensitive builds, 1376779-2 is a drop-in; for high-reliability or frequent re-mating, the thicker gold on 7-146256-0 is the better call.