1. Adds an audio amplifier to improve low volume issues with SSB single sideband reception, providing noticeable performance enhancement. Redesigned FM and HF bandpass filters for improved signal clarity. 2. Includes an ESD protection tube at the input terminal to protect against electrostatic discharge and strong signal interference during transmission in the UV band when using dual antennas. 3. Utilizes a 0.12mm thick FPC flexible circuit board for reliable, short-circuit-free installation. Speaker installation is not supported. 4. Equipped with high-quality, high-frequency wire-wound chip inductors offering high Q value, low internal resistance, and excellent filtering selectivity. 5. In dual-antenna configurations, an additional stage of bandpass filtering is integrated at the antenna input. Uses a feeder and SMA connector to connect to an HF antenna from the LED, without affecting UV band performance. The FPC board features a double-sided design for easier device integration. Compatible with K5/K6 models for installing S14732 FPC soft board to enable HF shortwave full-band and single sideband reception. Supports both single and dual antenna setups. Applicable Models: UV-K5, UV-K6 Note: Product appearance, color, and labeling may vary slightly between manufacturing batches, but functionality remains unaffected. Color: Orange Yellow Material: PCB Package Contents: 1 x Kit (set) Note: The package includes only the items listed above. Other accessories are not included. Lighting and display differences may cause slight variations in the color shown in images compared to the actual product. Measurement tolerance: 13 cm.