. Material: Plastic + Electronics 2. Size: The length of the wrist is about 20.5 cm. There are two buckles on the top. The adjustable diameter is about 3-4 cm. 3. Style: style color random (light bracelet) 4. Product use: no need to install another battery, directly open the switch, with three AG3 button batteries 5. Flashing, slow flashing, flashing, three lighting modes 6. Performance: sustainable light for more than 8 hours.