The MIL-DTL-38999 Series I connectors offer high-performance connectivity in harsh environments, featuring up to 128 contacts within an environmentally sealed insert. With an operating temperature range of -65 °C to 200 °C, these connectors ensure reliable functionality in extreme conditions. Available in various shell sizes and insert arrangements, they accommodate M39029 rear release crimp contacts for secure connections. The connectors come in durable aluminum shells with a choice of plating options, including cadmium-free finishes for RoHS compliance. Designed for military specifications, these circular receptacles with bayonet coupling are ideal for back panel box mounting applications, providing a rugged and reliable solution for demanding environments.