Easy to Use:Simply switch the battery on and off to operate.Re-usable over and over again, simply turn it off when not in use to conserve power. Color and Number: 2pcs Purple, 2pcs Green, 2pcs Blue, 2pcs Yellow, 2pcs Pink, 2pcs Transparent.Batteries Included in every bracelets OPP bag. Can be used immediately without preparations. For Everyone:Outside Diameter: 8.5cm, Inside Diameter: 6.5cm. Fits on every children, men and women.You can place them anywhere, on your wrists, arms, kid's ankles. Application:Best use for parties, birthdays, festivals, halloween, weddings, night activities, bonfires and more, increase the party atmosphere. Note:Not for children under 3 yrs who would put it in mouth.Please pay attention to your children.And the battery can be used for 4-6 hours. Product details Features: Color and Number: 2pcs Purple, 2pcs Green, 2pcs Blue, 2pcs Yellow, 2pcs Pink, 2pcs Transparent. All the bracelets have batteries inside already and have an on/off switch. Best use for parties, birthdays, festivals, halloween, weddings, night activities, bonfires and more, increase the party atmosphere. Specification: Material: acrylic. Outside Diameter: 8.5cm. Inside Diameter: 6.5cm. Batteries: 3 x AG3 batteries. Color:Pink,Transparent,Blue,Yellow,Purple,Green. Package Included: 12 pieces LED light bracelets. Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.