The MIL-DTL-38999 Series I connectors feature up to 128 contacts in an insert, designed for harsh environments with operating temperatures ranging from -65 °C to 200 °C. These connectors come in various styles including front and rear wall mount, as well as jam nut receptacles, all offering RFI grounding. With 9 shell sizes and 52 insert arrangements available, they utilize M39029 rear release crimp contacts in different sizes. Constructed with high-strength aluminum shells, they come with a choice of plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, including RoHS certified cadmium-free finishes. Ideal for military and aerospace applications, these connectors provide reliable performance with a service rating of I and a mating life of 500 cycles.