MIL-DTL-38999 Series I connectors offer reliable performance in harsh environments with up to 128 contacts sealed to withstand extreme temperatures ranging from -65 °C to 200 °C. Featuring front wall mount, rear wall mount, and jam nut receptacles, this connector family ensures secure connections. With 9 shell sizes and 52 insert arrangements, it accommodates various applications, utilizing M39029 rear release crimp contacts. Constructed with high-strength aluminum shells and available in different plating options, including RoHS certified finishes, these connectors guarantee durability and compliance. Suitable for military and industrial use, they provide reliable connectivity with gold-plated removable crimp contacts. The bayonet coupling design and A keyway polarization ensure easy and secure mating. Meeting MIL-DTL-38999 I specifications, these circular connectors are ideal for demanding environments requiring rugged performance.