The SL-500-SF is a laboratory-standard Precision Sleeve Dipole Reference Antenna professionally engineered by Fei Teng Wireless Technology Co., Ltd. (FT-RF) for high-fidelity Over-the-Air (OTA) performance testing and anechoic chamber range calibration routines. Operating continuously across the 400 MHz to 600 MHz UHF frequency spectrum, this premium reference instrument is meticulously optimized to satisfy the rigorous CTIA ±0.1 dB pattern symmetry thresholds, ensuring an exceptionally uniform omnidirectional radiation profile essential for critical chamber ripple test certification. Manufactured with strict industrial tolerances in Taiwan, its robust 380 g coaxial geometry integrates an internal quarter-wavelength sleeve balun that aggressively isolates the radiator structure from feed-cable induced currents, preventing pattern distortion and maintaining flawless Signal Integrity. Equipped with a standard premium SMA-Female port (with custom N-Female interfaces available upon request), this reference-grade radiator stands as the definitive choice for anechoic reflectivity evaluation, professional wireless efficiency benchmarking, and traceable low-gain reference calibration within commercial and defense testing networks.