The Molex 0430451229 is a 12-circuit, dual-row header from the Micro-Fit 3.0 43045 series, designed for board-to-cable/wire interconnects.
Position count and footprint match
With 12 positions loaded across two rows, this header matches a 12-circuit BOM line directly. The 3.00 mm pitch and 0.125" (3.18 mm) post length define the through-hole footprint — the same as the 10-position 0430451210 and the 14-position 0430451214 in the same series, so a board layout can scale across position counts without changing the pad geometry. The 0.390" (9.91 mm) insulation height clears most mating receptacle housings without interference.