Very handy universal radio with antenna. Can be powered by one 18650 battery or two at the same time. 00:00 Unboxing portable red mp3 radio speaker c-803 01:28 Retractable radio antenna 02:21 Radio support two 186 50 battery 04:09 Testing the radio with a charger 06:27 Testing the radio with a zayadzhny device Notes:the USB cable is just used for charge,it can't work if there is no battery Function: FM radio \TF card play \USB disk play \LED flashlight Parameter: FM frequency:87.5MHz~108MHz Rated power: 3w Frequency response: 20Hz~20KHz MP3 bit rate: 8K bps~320K bps Distortion: +\-0.55% SNR: 85db Size:120x25x60mm Voltage:5V\1000mA Battery: Support two 18650 battery It can work with one battery or two batteries, and it can last longer time with two battery, please consider how many batteries do you want. 1. How to charge: connect the USB cable to a phone charger or computer and then it will get charged; 2. How to use the FM radio: switch to the FM mode and long press the play key, it will search the radio station and save it automatically, only the first time you need to search the radio station, it can save 50 radio station and you can select them by the number key. 3. How to play music in the sd card or usb disk: insert a sd card or a usb disk and it will play it automatically, this device can insert two sd card, long press the "next" and "prev" key to fast forward / fast reverse A batter bass sound performance with the bass diaphragm design *Ask your questions in the comments* ⚠❓⚠ 👇👇👇