5/8 in x 1 1/2 inch Aqua Blue Glow in the Dark Glow Stick with Clip (1635ST)

How the "Glow in the Dark" works:

We use a proprietary mixture of phosphors that we source from around the world to bring bright and long lasting glow in the dark lighting options to those of you that depend on our products for work and play. Phosphors are rare earth materials that when exposed to UV light, contain electrons that are excited and emit energy in the form of visible light. Similar to charging and using a battery, once the phosphor's electrons are charged and start emitting energy in the form of visible light, the amount of energy in the electrons will decrease over time and the brightness / intensity of the visible light (the glow) will continue to decrease until the electrons are charged again. The materials we source will be able to be charged by UV light over and over again for 20 plus years.

As the charged material starts to emit light, it will decrease over several hours. The lengths of estimated time for the glow material to emit visible light are based the phosphors in the items considered “glowing” if the naked eye can identify the object has a glow at even the lowest level in a dark room. The stronger the UV light and the longer the length of time that the phosphors are exposed to the UV light, the brighter and longer the item will glow. In most cases, 8 minutes in direct sunlight is sufficient to produce a productive glow

Green Glow will last up to 18 hours depending on how much UV light you are able to expose it to and for how long. Sunlight, many flashlights, UV specific lights, and some cell phone flashlights can charge the glow material. Green is the glow that appears brightest compared to the other colors due to the human eye being particularly sensitive to green light.

Sky Blue Glow will last 8 to 12 hours depending on how much UV light you are able to expose it to and for how long. Sunlight, many flashlights, UV specific lights, and some cell phone flashlights can charge the glow material.

Aqua Blue Glow will last 12 plus hours depending on how much UV light you are able to expose it to and for how long. Sunlight, many flashlights, UV specific lights, and some cell phone flashlights can charge the glow material.

Pink Glow will last up to 4 hours depending on how much UV light you are able to expose it to and for how long. Sunlight, many flashlights, UV specific lights, and some cell phone flashlights can charge the glow material.