1. Product Description 1. Supports MP3 format, automatically plays upon poweron; red LED indicator updates during playback. 2. Compatible with USB flash drives (tested up to 32G) and TF cards (tested up to 16G). Default mode is TF card playback. If no TF card is detected, it automatically switches to USB mode. If both devices are connected, playback mode can be manually selected. Refer to the key operating instructions for details. 2. Features a USB power supply interface, allowing power input via a power bank or USB charger using a phone data cable. Also supports 3.7V lithium battery or 5V USB power supply. 3. Supports playback from TF cards (memory cards) or USB flash drives. No soldering required for speaker connections—modular design simplifies wiring and replacement. 4. quality audio output with a builtin 2W mono amplifier (3W under 5V power). Connects directly to speakers (recommended: 4 ohm 3W speaker). Includes a goldplated 3.5mm headphone jack for headphones or external audio devices.