Please remove the insulation sticker between the charging box and the earphone - Open the lid and you will see it - a transparent sticker with both ends rounded and connected in the middle with the words "REMOVE”.
2. Fully charge the charging box by use the charge cable.
3. Fully charge both of the earbuds ( put them in the charging box until the red indicator turns to blue ).
Tips:
1. Using the included USB cable to charge, the charge box will fully charge within 2 hours. (4 indicator lights will on and no blink means fully charged)
2. The both of earbuds will fully charge within 1~2 hours.