There's nothing worse than making a cup of tea, going back to your desk & completely forgetting about it, resulting in a cold up of tea. The USB (Universal Serial Bus) cup warmer plugs into your PC's USB (Universal Serial Bus) port & warms up to ensure that your tea or coffee is kept warm for up to an extra 30 minutes. The temperature is maintained at 40 degrees celcius even after an hour. You'll wonder how you ever lived without this cup warmer! Please note that this is an electrical item, do not let liquid come into contact with this device. This product cannot be used with plastic or paper cups, keep out of reach of children.