Feature:1. 1. Widely used: Suitable for beach umbrellas, fitness activities, outdoor sports, concerts, parties, festivals, bars, KTV, Christmas, Halloween, gifts, etc.2. 2. Improve safety: Better appreciate and visualize in low light or dark environments and avoid some potential traffic hazards.3. 3. Adjustable: Suitable for adults, boys and girls. One size fits most. You can adjust the size of the hat on the back.4. 4.3 Flash mode: bright, flash, off; bright colors: you can choose seven colors.5. 5. Easy to use: The switch "on/off" is hidden at the edge. A small sticker tells you where the switch is. Four modes can be selected: On, Slow Flash, Fast Flash, Off.Specification:Product Name: LED light hatPower: comes with 2* button battery, which can be replaced by yourself.Cap circumference can be adjusted: About 50-58cm/19.69*22.83inchProduct material: cotton twill fabricQuantity: 1pcsPackage List:1 pcs LED light hatNote:Due to the different monitor and light effect,the actual color maybe a slight different from the picture color.Please allow 2-3cm differs due to manual measurement.