MIL-DTL-38999 Series I connectors are designed for harsh environments, featuring up to 128 contacts in a sealed insert. Operating between -65 °C and 200 °C, they offer front and rear wall mount as well as jam nut receptacles with RFI grounding plugs. Available in 9 shell sizes and 52 insert arrangements, they use M39029 rear release crimp contacts in various sizes. Constructed with high-strength aluminum shells, plating options include cadmium and nickel finishes. These connectors are RoHS compliant, ensuring reliability in demanding applications.