The MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in an insert with environmental sealing. Operating between -65 °C and 200 °C, these connectors come in various configurations including front wall mount, rear wall mount, and jam nut receptacles, along with RFI grounding plugs. With 9 shell sizes and 52 insert arrangements available, they utilize M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 8. Constructed with high strength aluminum shells, they offer plating options like light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS certified cadmium-free finishes. Suitable for military and industrial applications, these connectors provide reliable connectivity in demanding conditions.