What it is and where it sits in the series
The Molex 430450423 is the 4-circuit, dual-row member of the Micro-Fit 3.0 43045 family — a 3.00 mm pitch header designed for board-to-cable power and signal distribution. Right-angle through-hole mounting with a board-lock feature gives it positive retention in the PCB during wave or hand-solder assembly and in service. The four-wall shroud and locking ramp on the header body engage the matching receptacle housing for a vibration-rated mechanical lock that a friction-fit header cannot guarantee.
Key ratings and what they mean for the build
Rated 8 A per contact at 600 V, suitable for power and signal distribution across automotive, industrial, and medical applications. The per-contact current rating means each circuit carries its own 8 A budget independently of adjacent circuits in the same housing. The split plating is the series signature worth flagging on every BOM check. The mating face carries gold at 30.0 µin (0.76 µm) over nickel — that is the wear surface and the low-resistance first-mate interface. The solder tails are thick tin at 100.0 µin (2.54 µm), optimized for solderability and solder-side corrosion resistance rather than repeated mating. For a board-to-cable header mated and unmated in the field, the gold-on-mating surfaces and the tin tails together give the right lifecycle balance: the connector sees its wear on the harness side where the receptacle lives, while the PCB termination stays permanently made. Operating range is −40°C to 105°C with UL94 V-0 rated LCP housing material — sufficient for most automotive under-dash and industrial enclosure environments. The insulation height of 0.290 inch (7.37 mm) sets the board-profile constraint for any enclosure opening or potting dam downstream of the header.