Review on European VINTAR International American Outlets by Rich Rickenbaugh

They work exactly as intended. You plug them into a round, two-pin, high-voltage European socket, and all automatic sensor devices can be plugged directly into it. The best part for most tech travelers these days is that the USB ports on top allow me to connect a fan to an outlet and my Kindle and iPhone or other devices to the USB ports on the top of the ports. Each plug has 2 USB ports on top, allowing you to install 6 charging stations for devices on three plugs. Anyone who's traveled abroad in this age of devices knows that trying to plug in a CPAP, a phone or two, a tablet, and maybe an e-reader can be pretty limited these days. Just remember that they don't change the voltage, just the shape of the plug. So whatever you connect to the plug changer should be rated for 220v from the start. If that is not possible then you will need a step down transformer which is a different piece of equipment. If you're not sure, check the owner's manual of any device you're taking with you on your trip, or call the manufacturer.