MIL-DTL-38999 Series II connectors feature up to 128 contacts in an insert, offering environmental sealing and a wide operating temperature range of -65 °C to 200 °C. These harsh environment 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 come with plating options like cadmium and nickel, meeting RoHS compliance standards. Suitable for military applications, these circular connectors ensure reliable performance in demanding environments.