MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in an insert with front and rear wall mount options. These connectors are environmentally sealed and can operate in temperatures ranging from -65 °C to 200 °C. They offer versatility with 52 insert arrangements and utilize M39029 rear release crimp contacts. Constructed with high strength aluminum shells, they come in various plating options such as cadmium and nickel. RoHS certified finishes are available. These connectors, part of the 38999 Series I, are ideal for applications requiring reliable electrical connectivity in demanding conditions.