Use these unique pebbles to line the edge of a flower bed or walkway in a decorative garden fish tank Glow lasts approximately two to three hours in full sunlight Quantity: 100 pieces/lot Dimensions: 2-3 cm/078-118 inches Colour: mixed/white/green/yellow/rose red/blue Material: Luminous Pigment + Resin Packaging Content: 50 pieces. It emits light by absorbing light source. It emits light for 8-12 hours each time, of which the first 1-2 hours is the strong light period. The received product does not glow because it does not emit light during the logistics process. It absorbs light and can glow again as long as it is exposed to sunlight or exposed to light for a period of time. 2Q: Why does it have sunlight during the day but not at night? Answer: Because the principle of night light is to absorb light and emit light, that is to say, it starts to emit light during the process of storing light. If it absorbs light during the day, but after dusk, it starts to emit light. The luminous period of the night light has ended, so you can only see a slight light, but when you turn on the light, you can see it is very bright 3Q: What is the brightest Colour of luminous stone? Answer: The luminous Colour of luminous stone is white, such as bright yellow, green, blue, green, etc. Other Colours are Coloured with yellow-green powder and Coloured powder. Toner will cover up the glow of the luminous powder. After being exposed to strong light for 3 hours, the pebbles can light up in the dark within 1-2 hours. Note: Due to differences between different monitors, the picture may not reflect the actual Colour of the item. Thank you