... usb cup warmer with usb hub 2),Good service. Competitive price. 3),Low voltage,Safe and reliable hot temperature. Type: usb cup warmer with usb ... & play automatic installation, easy installation, no driver required.3) USB powered, easy installation, no driver required, plug and play.4) On/off ... cupkeep cup warmkeep warm cupusb heating cupElectrically Heated Cup usb cup warmer with usb hub,usb heater