MIL-DTL-38999 Series I connectors feature up to 128 contacts in an environmentally sealed insert, designed for harsh environments with an operating temperature range from -65 °C to 200 °C. Available in various shell sizes, they offer front wall mount, rear wall mount, and jam nut receptacles, along with RFI grounding plugs. Utilizing M39029 rear release crimp contacts, they come in sizes 22D, 22M, 22, 20, 16, and 8 for coax and twinax applications. Constructed with high-strength aluminum shells, these connectors offer plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS certified cadmium-free finishes available. Suitable for military and industrial use, they ensure reliable connectivity with a service rating of I and a mating life of 500 cycles.