All parts need to be installed by yourself. The outer cover is transparent if the paper is torn off. The entire Bluetooth speaker kit is equipped with a USB power cord, and the Bluetooth circuit board is well welded. You only need to connect the cable and assemble the sound control board. The power supply can be powered by a mobile phone charger or a computer 5V power supply. The sound quality is better when using a 2A power supply. Function: 3.7-5V DC power supply to automatically play music, 3W+3W stereo power amplifier, support Bluetooth, support power-off memory, U disk to play music, can be powered by a power bank. Bluetooth Operation: Turn on the Bluetooth of the mobile phone, scan the device directly, find "XC046" and click connect. After disconnecting Bluetooth, it will automatically switch to U disk. Power amplifier size: 106x66x60mm Channel output: 2 channels Output power: 3w+3w Power supply voltage: DC 4.2-5v voltage 5v exceeding 5v will damage the module Rated current: 1.5A-2A. Material: Plastic+metal colour: As shown Package Contents: 4 x DIY Electronic Kit