The MIL-DTL-38999 Series I connectors feature up to 128 contacts in an environmentally sealed insert, ideal for harsh environments with an operating temperature range of -65 °C to 200 °C. Available in various mounting options, including front wall mount, rear wall mount, and jam nut receptacles, they meet stringent military specifications. With 52 insert arrangements and M39029 rear release crimp contacts in multiple sizes, these connectors offer versatility for diverse applications. Constructed with high-strength aluminum shells and plated in options like electroless nickel and cadmium finishes, they ensure reliable performance. RoHS compliant versions are also available, making them suitable for environmentally conscious projects.