Package include: 1pc X Necklace
Material: Alloy,Glow In dark
Total length (approx): 19.3 inches
How to use:Because the goods in the delivery of a few days in the express package can not absorb light, so it is necessary to absorb light.During the day in the sun or outdoor ultraviolet light, dark light.
The intensity of light and the length of time is different, luminous brightness will be different, about 30 minutes after irradiation can send several hours of light. 
