1. With the USB power supply interface, power can be provided via a mobile adapter or USB charger through the phone's data cable. It can also use a 3.7V lithium battery and a USB 5V power supply. 2. sound quality, builtin 2W mono amplifier (5V power supply up to 3W), directly connectable to a speaker (recommended with a 4ohm 3W speaker), goldplated 3.5mm headphone jack for headphones or external audio connection. 3. Product Description: Supports MP3 format, automatic playback on poweron, red LED indicator updates during playback. Supports Udisk playback mode (tested with 32G), TF card mode (tested with 16G). Defaults to TF card mode on startup; if no TF card is detected, it automatically switches to Udisk mode. If both devices are connected, the playback mode can be manually selected. Refer to the main user manual for details. 4. Supports TF card (memory card) and Udisk playback modes; no soldering required for horn terminals, making wiring convenient; modular design allows for easy modifications.