High quality glowing mixture was used in the process and it will keep the image glowing for hours! I tested this personally myself with the glow lasting at least 6 hours. After the initial charge the glow dims slightly but afterwards it will continue to glow for a really long time. The best way to charge these up is through a mini UV torch. (Please note RED parts of images does not glow as much or as bright as other colours.)

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• This is a handmade Personalized necklaces
• Necklace material: Metal , Glass
• pendant size：20mm Chain length:24 inches ( Can customize the chain length )

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