2020 Christmas USB Fairy Lights LED String Lights Music Sync Bluetooth APP Phone Indoor Outdoor Twinkle Lights 32.8FT Hanging Curtain String Lights Color Changing Starry Lights. Features: USB charging: The Led String Fairy Lights is no need battery, energy saving and environmental performance. Sync to Music & Timer: The copper wired string light, easily twisted,with sync to music will change the speed with the music rhythm,and the timer could help to save more electricity. APP Controlled Starry lights: With the App, Download APP 'LedBle' ( IOS /Android),connect the light via Bluetooth you can easily change the color and the mode of lights, NO NEED a remote controller. The starry light is dimmable within 12m range with the app. Brightness Adjustment: The led string lights could drag the brightness adjustment button on the APP to achieve any degree of dimming or glowing, instead of choosing from several brightness levels. Memory Function: The fairy string lights is with memory function,will keep working and flashing mode even if the Bluetooth is out of connect,as well as keeping last of the timer setting,no need to worry about wasting electricity. Specifications: Item Weight: 3.2 ounces. Length: 5m 50 LEDS. 10m 100LEDS. 15m 150LEDS. 20m 200LEDS. Package Dimensions: 3.6 x 3.6 x 1.7 inches. Power Source: Battery-powered, Plug-in_electric. Type of Bulb: LED. Batteries Required: No. Package Included: 1 X 50/100/150/200LEDs Fairy String Lights. Warm Tips: 1. About connecting the Bluetooth: Don't connect the device on your phone Bluetooth from Settings, if so,please exit out or 'Forget This Device', cause when connected from phone Settings, the devices could not be searched and found on app(LED BLE). 2. About playing music: Palying your own music(under IOS system),it needs to download the music from iTunes on computer,then insert the music to APP(LED BLE) to play it.(If Android system),the music could be insert from other music APP to the APP(LED BLE)directly