Nextglo, key id tag, glow in the dark technology, allows maximum glowing in variety of colors, perfect for visibility & identification, high performing, long persistence glow charges in minutes & lasts for hours, ability to be charged from any light source, including both natural & artificial sources, durable write on tags, you can use a permanent marker to identify your tags & know that they will be readable day or night, easily attach & detach using the included s-biner micro locks.