MIL-DTL-38999 Series II connectors feature up to 128 contacts sealed for environmental protection, with an operating temperature range of -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 with 52 insert arrangements, they utilize M39029 rear release crimp contacts. Constructed with aluminum shells and offered in multiple plating options, such as electroless nickel and cadmium finishes, they ensure reliable performance in demanding applications. With a bayonet coupling mechanism and gold-plated removable crimp contacts, these connectors provide secure and durable electrical connections. Suitable for military and industrial use, they offer a service life of 500 cycles and meet stringent environmental resistance standards.