Product Description: Supports MP3 playback, automatically plays when powered on, with a red LED indicating playback status. Supports U-disk (tested over 32G) and TF card (tested 16G) playback modes the default mode is TF card when powered on. If the TF card is not present, it automatically switches to U-disk mode. If both devices are installed, you can manually set the playback mode refer to the button function instructions. Button controls for track skipping, volume , pause or play, and mode switching. Note: "Long press" duration is approximately 2 seconds. If using U-disk mode, a 5V power supply is recommended, as some U-disks do not support 3.7V power. Product Specifications Power Supply Range: 3.7 - 5.5V Product Size: 45mm x 36mm Exquisite double-board design with a copper surface for stable and reliable performance. Anti-static bag packaging to prevent damage due to static electricity during delivery. Material: metal Color: blue Package includes: 1 x Mp3 lossless decoder board Note: Light and different displays may cause the color of the item in the picture to be slightly different from the real thing. The allowable measurement error is 1-3 cm.