D38999/26FE8SN is a MIL-DTL-38999 Series III subminiature connector designed as a straight plug with environmentally sealed construction for rugged, harsh environment applications. The connector features electroless nickel plating on the shell with normal keying configuration, providing excellent corrosion resistance and environmental sealing. It utilizes a threaded 360° turn coupling mechanism and supports multiple contact sizes (23, 22, 20, 16, 12, 10, 8) with a maximum of 187 signal contacts, accommodating various contact styles including crimp, solder cup, and PCB tail configurations. The connector operates across a wide temperature range of -65°C to +200°C depending on shell finish, with a standard durability rating of 500 mating cycles. This connector is widely used in aerospace, defense, and marine applications where reliable, environmentally sealed connections are critical for mission-critical systems.