To activate your LED Gold Sequin Bow Tie, find the sticker on the back of bow tie. Push there for multiple options: flash, blink, or a calm steady light. Dimensions: Neck Strap Length: Max 25 in. Bow Width: 5 in. Bow Height: 3.75 in. Sequin Gold Bow Tie with Amber LEDscome ready to use, batteries are NOT replaceable.