Before use, power detection is carried out, press the mobile power start button, the green LED indicator shows the current battery power, the green LED indicator blinks, indicating that the power is insufficient, if the LED indicator does not show, it means that the power has been used up and needs to be charged or the product fails. If the battery is low, charge the power bank first. If you have enough power go straight to step three. When the power bank is sufficient, the phone or tablet can be charged