The MIL-DTL-38999 Series II connectors are engineered for rugged environments, featuring up to 128 contacts in an insert for robust connectivity. With a wide operating temperature range from -65 °C to 200 °C, these connectors are ideal for harsh conditions. Available in various mounting options such as front wall, rear wall, jam nut, and box mount receptacles, they offer flexibility in installation. The connectors, made of aluminum, come in 9 shell sizes and 52 insert arrangements, accommodating diverse applications. Utilizing M39029 rear release crimp contacts, they ensure secure connections. Plating options include cadmium-free finishes, meeting RoHS requirements. These connectors, with gold-plated contacts, guarantee reliable performance with a mating life of 500 cycles. Designed for environment-resistant applications, they provide excellent conductivity and ingress protection, making them essential for military, aerospace, and industrial use.