Targeted Heat Therapy: Carbon fiber far infrared heating, 5V low voltage, safe and stable. Fast heating up within few seconds, provides soothing warmth to wrist and hand, promote circulation, relieve pain and increase the hand flexibility. 3 Temperature Settings: Adjustable 3 temperature levels with indicator light, one button control. Green light-about 122, Blue light-about 140, Red light-about 158. One Size Fits All: Universal sizing for left or right hand. sufficient to cover palm and back of hand & wrist. Insert the thumb into the hole and wrap the brace around the wrist, adjustable size by the hook and loop. USB Powered: The heated brace for wrist powered by usb cable which can easily been plugged to any PC, power bank, car charger and USB adapter. Plug and play. Solve Different Wrist Problems: This usb heating pad can 360wrap the wrist and offers therapy heat, great for Repetitive strain injury, Carpal Tunnel Syndrome, Tendonitis or anyone who suffers wrist & hand pain due to long time working/ driving/ holding the baby. .