The 755-78-9 is a BNC plug connector manufactured by Winchester Electronics, designed for high-frequency RF and microwave applications requiring reliable impedance matching and low insertion loss. It features a nominal impedance of 50 ohms with a working voltage rating of 500 VRMS and operates across a frequency range from DC to 4 GHz, achieving a VSWR of 1.30 maximum across the 0–4 GHz band. The connector exhibits insertion loss of 0.05 dB maximum from DC to 2.8 GHz and 0.12 dB maximum from 2.8 to 5.0 GHz, ensuring minimal signal degradation in precision measurement and communication systems. The connector is constructed with a Teflon insulator, beryllium copper outer contact, and brass components with selective gold and nickel plating for corrosion resistance and optimal electrical performance. It is compatible with Boeing BMS13-65 and Adams Russell FC14Z cables, making it suitable for aerospace, military, and telecommunications applications where signal integrity and environmental durability are critical.