The WI-15-UG-20 is a laboratory-grade Millimeter Wave (mmWave) Standard Gain Horn Antenna professionally engineered by Fei Teng Wireless Technology Co., Ltd. (FT-RF) for high-fidelity directional transmission, antenna calibration, and advanced high-frequency diagnostics across the continuous 50 GHz to 75 GHz V-Band spectrum. Meticulously optimized to enforce exceptional boresight path stability, this premium horn antenna delivers an elevated nominal directive gain profile of 20 dBi combined with an exceptionally low maximum V.S.W.R threshold of 1.3 : 1. Precision CNC machined from high-grade structural aluminum alloy in Taiwan, the advanced millimeter-wave launch architecture establishes a highly concentrated directional radiation footprint, providing narrow matching -3dB beamwidths of 17° in both the H-plane and E-plane matrices. Equipped with a standardized precision UG Flange layout, this ultra-lightweight 20 g instrument ensures flawless electromechanical alignment, eliminates boundary signal leakage, and safely manages continuous wave power loads up to 150 Watts (CW). Its optimized microscopic structural tolerances avoid destructive field distortion modes, rendering it the definitive choice for next-generation 5G/6G wireless research networks, automated spectrum surveillance matrices, advanced millimeter-wave system characterization, and mission-critical Signal Defense laboratory verification setups.