The Earthing Outlet Checker, tests the electrical outlets (Type I) in your home to verify that they are grounded before using your earthing products.
Type I outlets are used in:
American Samoa, Argentina, Australia, China, El Salvador, Fiji, Guatemala, Kiribati, Nauru, New Zealand, Okinawa, Panama, Papua New Guinea, St. Vincent, Tajikistan, Tonga, Uruguay.