MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in an insert with front wall mount, rear wall mount, and jam nut receptacles. Operating in temperatures ranging from -65 °C to 200 °C, these connectors are environmentally sealed for reliable performance. Utilizing M39029 rear release crimp contacts in various sizes, they offer versatility with 52 insert arrangements available. Constructed with high-strength aluminum shells, they come in different plating options including cadmium and nickel finishes. These connectors, compliant with RoHS standards, ensure durability and conductivity with a service rating of I, making them ideal for demanding applications.