What this is
The Molex 430450425 is the 4-circuit member of the Micro-Fit 3.0 43045 series — a dual-row 3.00 mm pitch header rated 8 A per circuit at 600 V. The mating face carries gold plating at 15.0 µin (0.38 µm) over the brass contact; the solder tail is hot-dipped tin at 100.0 µin (2.54 µm). Four-wall shrouding and a locking ramp are standard, and the header ships with board guide and board lock features for automated assembly retention.
What the ratings mean for your fit
The 8 A per circuit rating puts this squarely into power-distribution territory for a 3.00 mm pitch — the current ceiling is governed by the contact plating grade and the LCP housing's thermal limits, not the pitch itself. The gold-on-mating / tin-on-solder split is the standard for this series: the precious metal on the plug interface maximises mating-cycle life and maintains low contact resistance at first mate, while the thick tin on the tail survives multiple solder reflow exposures without degradation. The 4-wall shroud and locking ramp prevent mis-mating in dense harness runs. Board lock and board guide together hold the header true during wave or selective solder and resist peel forces once the board is populated — relevant if the assembly sees field service or rework cycles.
Where this class is used
Micro-Fit 3.0 headers are a go-to power interconnect in automotive control modules, industrial automation controllers, and medical instrument panels — anywhere a compact 3.00 mm dual-row footprint must carry meaningful current without a full-size connector. The 4-circuit count suits low-channel power rails, auxiliary bus connections, or actuator feeds where the full multi-position range of the series is overkill.
Against its same-series peers
The 4-position 0430450425 and the 6-position 0430450625 share every feature with the seed: board lock, board guide, 4-wall shroud, locking ramp, and the same plating stack. Circuit count is the only delta between them and this header — match the position count to your board's power channel count.