MIL-DTL-38999 Series I connectors feature up to 128 contacts housed within an insert, offering environmental sealing and a wide operating temperature range from -65 °C to 200 °C. This harsh environment connector family includes front and rear wall mount options, as well as jam nut receptacles and RFI grounding plugs. With 9 shell sizes and 52 insert arrangements available, they utilize M39029 rear release crimp contacts in various sizes, including 22D, 22M, 22, 20, 16, and 8 (coax and twinax). Constructed with high-strength aluminum shells, these connectors come with plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, with RoHS certified cadmium-free finishes also offered. Suitable for military applications, these connectors are designed for durability, with a straight plug shell style, contact gender specified as female, and a mating life of 500 cycles. The environment-resistant design, along with a conductivity rating of conductive and a service class of M, makes them ideal for demanding industrial and military environments.