MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in an insert. These circular connectors come in various styles including front wall mount, rear wall mount, and jam nut receptacles, all offering RFI grounding options. With a wide operating temperature range of -65 °C to 200 °C, they are suitable for demanding applications. Available in 9 shell sizes and 52 insert arrangements, these connectors use M39029 rear release crimp contacts in different sizes. Crafted from high-strength aluminum, they come with plating options like cadmium olive drab, electroless nickel, and black anodized aluminum. Meeting MIL-DTL-38999 I military specifications, these connectors are reliable for use in environments that require durability and performance.