Targeted Heat Therapy: Graphene heating technology and release far-infrared rays promotes blood circulation to loosen and relax tense muscles. First Turn on the power bank, connect the USB in the scarf, and then press 3s button to switch on the scarf. If you have any questions, please feel free to contact us!!! Tips: At the first use, it is recommend to charge 4-6 HOURS until 4 indicator light are no longer flashes.