MIL-DTL-38999 Series II connectors feature up to 128 contacts, offering environmental sealing and a wide operating temperature range from -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 utilize M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 12. Constructed with aluminum shells, they come with plating options such as electroless nickel and cadmium finishes. Designed for military specifications, these connectors are reliable with a mating life of 500 cycles, ideal for applications requiring environment-resistant connectivity.