This earphone emits light without battery after it has absorbed the light-Different colors during the day, but at night it is a green light effect-If you use it for the first time, then keep it in the light of the sun-Then it gives a light effect in the dark

Frequency: 20-20,000 Hz sensitivity: 106d BImpedance: 16 Oh cable length: 1.2 m plugbox 3.5 mm