DIY: Portable Mp3/Mp4 Bluetooth Speaker

Homemade boombox, radio, sd/usb mp3/mp4 player Mp4 board(New V): Or Mp4 big screen: Speakers: Amp module: Passive radiators: 18650 Batteries: 18650 holder: 4S PCB: 4S meter: DC module: or DC/DC isolator: Mini switch: Power jack: Drill Bit used : or: Multi charger: Multimeter: