200mAh Lithium battery included. Our led cup coasters were equipped with an accelerometer and light-dependent resistor (LDR) to save power.
Rechargeable. The led cup holder light will automatically turn on in the dark when it senses vibration, and automatically turn off in 15 seconds when senses no vibration.
Tested before ship.
Package included: 2x Led cup coaster; 1x 2in1 USB cable; 1x user instruction; 1x package.