To activate your Fiber Optic Merry Christmas Headband, flip the switch located at the top of the headband. Words do not light up – they are covered in silver glitter. LED colors will automatically change; there are no other light options other than an array of beautiful rainbow changing colors. NOTE: Due to packaging that will save you money on shipping, headbands require light assembly. Fiber Optics arrive separate, so just plug them into the 2 spots provided on the headband. Dimensions: Height 7.50 in. Width 4.87 in. Fiber Optics Length 4.0 in. LED Colors: Rainbow Headband Colors: Assorted packs of Red and Green. Headbands include 3 replaceable AG13 Batteries. Packaging: Retail ready, individual poly bags, 12 pieces per inner box – 144 pieces per carton.