Pack of 100 – 3D Stars Glow In The Dark Wall Stickers Luminous Fluorescent Wall Stickers For Kids Baby Room Bedroom Ceiling Home Decor

It adsorbs light and glows in the dark. So you must put it in the sun to absorb much light. Or you can also turn on the lights to let it absorb enough lamplight. When you turn off the light and go to bed, it will glow in the dark.