MIL-DTL-38999 Series I connectors feature up to 128 contacts in an insert, designed for harsh environments with an operating temperature range of -65 °C to 200 °C. Available in various configurations including front and rear wall mount, jam nut receptacles, and RFI grounding plugs, they offer versatility for different applications. With 9 shell sizes and 52 insert arrangements, these connectors utilize M39029 rear release crimp contacts, ensuring reliable connectivity. Constructed with high-strength aluminum shells, they come in multiple plating options such as cadmium and nickel for enhanced durability. Meeting military specification MIL-DTL-38999 I, these circular receptacles are ideal for demanding environments where rugged performance is essential.