Molex Mini-Fit Jr. 4.2mm Connector

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Molex Mini-Fit Jr. 4.2mm Connectors — Housings, Headers, Crimp Terminals & Cable Assemblies The Molex Mini-Fit Jr. series (5557/5559, 4.2mm pitch) is the global standard for ATX PC power supplies, server motherboards, and high-current industrial applications. Rated at 9A per contact / 600V AC/DC , it is the highest-current connector in the Molex wire-to-board range — trusted by engineers worldwide for 24-pin ATX, 4-pin CPU, 8-pin EPS, and industrial power rail connections. Products in This Collection 5557-NN Receptacle Housings — Wire-side receptacle, 2–24 circuits, dual-row, natural nylon 5559-NN PCB Headers — Top-entry through-hole headers, tin-plated contacts 5556 Crimp Terminals — AWG #18–#24, tin-plated, for 5557 housings Pre-Crimped PVC Cable Assemblies (UL1007 18AWG) — Single-head, same-side-head, dual-row extension; multiple pin counts Pre-Crimped Silicone Cable Assemblies (UL3239 20AWG) — 200°C / 3KV / 5A rated, single-head & male-female extension Connector Kits — Assorted housings, headers, terminals and pre-crimped cables Key Specifications Pitch: 4.2mm | Circuits: 2–24 pin (single & dual row) Current rating: 9A per contact | Voltage: 600V AC/DC Wire gauge: AWG #18–#24 | Temperature: −40°C to +105°C Silicone variant: 200°C / 3KV / 5A (UL3239 20AWG) for high-temp environments Material: PA66 nylon housing | Contact: tin-plated copper alloy Compliance: UL recognized · RoHS2 compliant Why Choose Molex Mini-Fit Jr.? ✅ 9A per contact — the highest current rating in the Molex wire-to-board range ✅ ATX / EPS / CPU power standard — 24-pin, 4-pin, 8-pin PC power connectors all use Mini-Fit Jr. ✅ Dual-row up to 24 circuits — maximizes density for multi-rail power applications ✅ Silicone UL3239 option — 200°C / 3KV rated for automotive and high-temperature use ✅ Positive latch lock — secure mating under vibration and mechanical stress ✅ RoHS2 compliant — suitable for consumer, industrial and automotive electronics Typical Applications ATX PC power supply