MIL-DTL-38999 Series II 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. These 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, they offer plating options such as electroless nickel and cadmium finishes. RoHS compliant versions are also available. Designed for military specifications, these connectors provide reliable performance with gold-plated contacts, suitable for applications requiring durability and conductivity in demanding settings.