D38999/26WB98SN is a MIL-DTL-38999 Series III subminiature connector designed as a straight plug with EMI spring fingers for rugged, harsh environment applications in aerospace, defense, and marine industries. The connector features a threaded 360° turn coupling mechanism and is environmentally sealed with scoop-proof design, offering hermetic and filter versions for enhanced protection. It supports multiple shell materials including stainless steel, aluminum, and composite, with various plating options such as electroless nickel, nickel PTFE, black zinc-nickel, and olive drab cadmium to meet specific corrosion resistance requirements. The connector accommodates up to 187 maximum signal contacts across nine shell sizes (9 through 25), with contact sizes ranging from 8 to 23 and supporting crimp, solder cup/eyelet, and PCB tail contact styles. Operating temperature range extends from -65°C to +200°C depending on shell finish selection, with a standard durability rating of 500 mating cycles and higher durability versions available. This connector is ideal for applications requiring reliable electrical connections in demanding environments where environmental sealing, EMI control, and long-term durability are critical.