MIL-DTL-38999 Series I connectors feature up to 128 contacts in an environmentally sealed insert, designed for harsh environments with an operating temperature range of -65 °C to 200 °C. This connector family includes front and rear wall mount as well as jam nut receptacles, along with RFI grounding plugs. With 9 shell sizes and 52 insert arrangements available, they utilize M39029 rear release crimp contacts in various sizes, including coax and twinax. Constructed with high strength aluminum shells, these connectors offer plating options such as cadmium and nickel, with RoHS certified finishes. Suitable for military and industrial applications, they ensure reliable performance with features like bayonet coupling and conductive socket contacts, meeting rigorous standards for environment resistance and durability.