MIL-DTL-38999 Series II connectors, featuring up to 128 contacts in an insert, are 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. Constructed with aluminum shells and offering multiple plating options, such as gold and electroless nickel, they ensure reliable performance in demanding applications. With RoHS compliant finishes, these circular connectors are ideal for military and industrial use.