This adapter will let you plug into a US 2-prong power adapter in the following locations:American Samoa, Argentina, Australia, China, El Salvador, Fiji, Guatemala, Kiribati, Nauru, New Zealand, Panama, Papua New Guinea, Saint Vincent and the Grenadines, Tajikistan, Tonga, Uruguay-- and also the city of Okinawa, Japan.Compatible with all the power adapters Adafruit carries as all are 110-240V compatible!