MIL-DTL-38999 Series I connectors feature up to 128 contacts in an insert, designed for harsh environments with operating temperatures ranging from -65 °C to 200 °C. Offering front wall mount, rear wall mount, and jam nut receptacles with RFI grounding plugs, they come in 9 shell sizes and 52 insert arrangements. Utilizing M39029 rear release crimp contacts in various sizes, including coax and twinax, these connectors are housed in high-strength aluminum shells with plating options such as cadmium finishes and black anodized aluminum. RoHS certified options are available, ensuring compliance with environmental standards. Perfect for military and industrial applications, these connectors provide reliable performance with features like bayonet coupling and conductive contact styles, suitable for environment-resistant box and bulkhead mounting receptacles.