Product Features: [Dual-System Reception] The ESP138 is a dual-architecture professional radio, utilizing both the TEF6686 system (open-source DSP algorithm) and the ESP32-SI4732 system (full-band coverage), operating independently. Note: The TEF6686 system supports open-source firmware upgrades, while the SI4732 system's firmware is locked and cannot be flashed. Frequency: In TEF6686 mode: Coverage: FM (65-108MHz) / LW (144-513kHz) / MW (520-1720kHz) / SW (1700-27000kHz). Air Band and SSB are not supported. In SI4732 mode: Coverage: LW (153-500kHz) / MW (520-1710kHz) / SW (1730-30000kHz) / FM (64-108MHz) / SSB (1730-30000kHz) / Air Band (50-200MHz, native support for 118-138MHz). Supports Air Band (AIR) and Single Sideband (SSB) without the need for additional equipment. Color: Black / Silver Material: Aluminum Alloy Package Contents: 1 x Radio 1 x TYPE-C charging cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.