MIL-DTL-38999 Series I connectors feature up to 128 contacts in an insert, designed for harsh environments with an operating temperature range of -65 °C to 200 °C. This connector family includes front wall mount, rear wall mount, and jam nut receptacles, along with RFI grounding plugs. Available in 9 shell sizes and 52 insert arrangements, they utilize M39029 rear release crimp contacts in various sizes. Constructed with high strength aluminum shells, they offer plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS certified cadmium-free finishes. Suitable for military applications, these connectors provide reliable performance with their bayonet coupling and environmentally sealed design, ensuring durability in demanding conditions.