The WI-159-UDR-25 is a laboratory-grade microwave Standard Gain Horn Antenna professionally engineered by Fei Teng Wireless Technology Co., Ltd. (FT-RF) for ultra-high performance directional transmission, satellite ground links, and anechoic calibration routines across the 4.9 GHz to 7.05 GHz C-Band spectrum. Meticulously optimized to enforce exceptional boresight path stability, this premium horn antenna delivers a commanding nominal directive gain profile of 25 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 large-scale horn flare geometry establishes an ultra-focused and symmetric radiation footprint, providing narrow -3dB beamwidths of 8° in both the H-plane and E-plane matrices. Equipped with a standardized rectangular square UDR Flange layout, this robust 4.3 kg instrument ensures flawless leak-free electromechanical coupling and safely manages continuous wave power loads up to 3000 Watts (CW). This optimized layout avoids destructive field distortion modes, making it the definitive choice for long-range link calibration, satellite tracking, intensive EMI/EMC testing scenarios, and mission-critical Signal Defense reference arrays.