MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in an insert with excellent environmental sealing. Operating flawlessly between -65 °C and 200 °C, these connectors come in various styles including front wall mount, rear wall mount, and jam nut receptacles 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, including coax and twinax options. Crafted from high-strength aluminum, they offer plating choices 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 guarantee durability with a service rating of I and a mating life of 500 cycles. The contact plating in gold ensures optimal conductivity, making them ideal for demanding environments.