MIL-DTL-38999 Series I connectors feature up to 128 contacts in a sealed insert, designed for harsh environments with an operating temperature range of -65 °C to 200 °C. Available in various shell sizes and insert arrangements, they offer rear wall mount, front wall mount, and jam nut receptacles, along with RFI grounding plugs. These connectors utilize M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 8, including coax and twinax options. Constructed with high-strength aluminum shells, they come in plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS compliant finishes available. Ideal for military and industrial applications, these connectors provide reliable performance with male pin contacts, bayonet mating, and a service rating of I for environmental resistance.