When I turn on the balls light up the LEDs emit the color of the stems, selected from several possibilities, but the peculiarity of Glo is that you can remove the ball from the base. Once removed will become and remain bright green fluorescent for about 30 minutes. In this way you can put them scattered room as you wish, and within 30 minutes of light you have the time to fall asleep. The balls are phosphorescent, do not emit heat and do not break when falling to the ground as they would if they were electronic.
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