2.1 channel output (satellites + subwoofer)
Bluetooth enabled for wireless audio streaming.
USB input (play music directly from USB flash‐drive)
SD / MMC card slot for direct playback.
AUX input (likely 3.5mm) and/or RCA, plus FM radio support.
Remote control for convenience of adjusting volume, input, etc.
Built-in amplifier in the subwoofer unit (so satellites are passive).