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. Offered in various configurations including front wall mount, rear wall mount, and jam nut receptacles, they ensure secure connections in demanding applications. These connectors come in 9 shell sizes and 52 insert arrangements, with M39029 rear release crimp contacts available in different sizes. Constructed with high-strength aluminum shells, they are plated with options like electroless nickel and cadmium finishes. RoHS compliant versions are also available, meeting environmental standards. Ideal for military and industrial use, these connectors provide reliability and durability in critical systems.