MIL-DTL-38999 Series II connectors feature up to 128 contacts in an insert, designed for harsh environments with an operating temperature range of -65 °C to 200 °C. These environmentally sealed connectors come in various configurations including front and rear wall mount, jam nut, and box mount receptacles. Available in 9 shell sizes and 52 insert arrangements, they use M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 12. Constructed with aluminum shells and offering plating options such as light iridescent yellow cadmium, olive drab cadmium, electroless nickel, and black anodized aluminum, these connectors meet stringent military specifications for reliability in demanding applications. RoHS compliant finishes are also available, ensuring environmental responsibility.