MIL-DTL-38999 Series II connectors are designed for harsh environments, with up to 128 contacts housed in an insert. These connectors are environmentally sealed, capable of operating in temperatures ranging from -65 °C to 200 °C. Featuring various mounting options like front wall, rear wall, jam nut, and box mount receptacles, they offer versatility for different applications. Available in 9 shell sizes and 52 insert arrangements, they use M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 12. Constructed with aluminum shells and offering plating options such as electroless nickel and cadmium finishes, these connectors ensure durability and reliability. Ideal for military and industrial use, they provide secure and efficient electrical connections in demanding conditions.