To activate your Light Up Angel Halo Headband, press the black button located on the battery pack. Steady on, and blinking. Dimensions: Halo Diameter: 5.5 in. LED Colors: 6 White Light Up Angel Halo Headbands come ready to use with 2 replaceable 3 AG13 Batteries. Packaging: Individually wrapped, poly bag – 12 pieces per bag- 96 pieces per carton.