The HS-028-UBR-25-NA is a high-performance Ka-Band Standard Gain Horn Antenna professionally engineered by Fei Teng Wireless Technology Co., Ltd. (FT-RF) for the WR-28 waveguide standard. Operating across the expansive millimeter-wave spectrum of 26.5 GHz to 40.0 GHz, this premium antenna delivers a consistent and precision-calibrated nominal gain profile of 25 dBi with narrow-beam precision combined with an exceptionally low maximum V.S.W.R threshold of 1.3 : 1. Featuring a Direct Waveguide Input with a standardized UG-599/U (UBR Style) flange layout, it ensures optimal structural impedance coplanarity and ultra-low-loss power transfer, safely managing continuous wave power loads up to 500 Watts (CW). Precision CNC machined from high-grade structural aluminum alloy in Taiwan, the specialized launch geometry creates highly focused 10° horizontal and 9° vertical radiation envelopes to maximize boresight resolution. It stands as the definitive choice for millimeter-wave EMI/EMC testing architectures, advanced 5G system parameters validation, high-bandwidth satellite communication networks, and mission-critical laboratory anechoic testing environments demanding uncompromised performance parameters.