MIL-DTL-38999 Series II connectors, designed for harsh environments, feature up to 128 contacts in an environmentally sealed insert. Operating between -65 °C and 200 °C, these 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. Constructed with aluminum shells and offering multiple plating options, such as cadmium and nickel, they ensure reliable performance. With a bayonet coupling and gold contact plating, they provide secure connections with a mating life of 500 cycles. RoHS compliant finishes are also available, making them suitable for a wide range of applications.