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 of -65 °C to 200 °C. The connector family includes front wall mount, rear wall mount, and jam nut receptacles, as well as RFI grounding plugs, offering versatility in installation. Available in 9 shell sizes and 52 insert arrangements, these connectors utilize M39029 rear release crimp contacts in various sizes, including coax and twinax options. Constructed with high strength aluminum shells, they come with plating choices such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS compliant cadmium-free finishes also available. Suitable for military and industrial applications, these connectors provide reliable connectivity with gold-plated contacts and a bayonet coupling mechanism for secure mating.