The MIL-DTL-38999 Series I 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. Available in various shell sizes and insert arrangements, these connectors come in high-strength aluminum shells with options for RoHS-certified cadmium-free finishes. Offering front wall mount, rear wall mount, and jam nut receptacles, they use M39029 rear release crimp contacts in sizes 22D, 22M, 22, 20, 16, and 8. With gold contact plating, bayonet coupling, and a maximum mating life of 500 cycles, they provide reliable connectivity for military and industrial applications.