This earphone will glow ?without any Battery?after it absorbs the light.So if it doesn't glow、 please take it to the bright place for a few hours??or put it under the light for about 10 minutes、then you can see it glow when you take it in the dark place or at night.1).Different colors?in the daytime、 but at night the light effect is the same、 showing green luminous effect. If the luminous effect is not very good、 recommend light irradiation、 the luminous effect will be very good2).For the first use、please put it near by light or under sun for some moment、then it will glow in the dark?Specifications:?Frequency: 20-20.000 Hz?Sensitivity: 106dB?Impedance: 16 Oh?Cable Length: 1.2m?Plug: 3.5mm?Package:?1x Zipper Earphone